No. 2007-04-A

OFFICE OF ECONOMICS WORKING PAPER

U.S. INTERNATIONAL TRADE COMMISSION

Michael J. Ferrantino 

U.S. International Trade Commission 

Zhi Wang 

U.S. International Trade Commission 

April 2007 

The authors are with the Office of Economics of the U.S. International Trade 

Commission. Office of Economics working papers are the result of the ongoing 

professional research of USITC Staff and are solely meant to represent the 

opinions and professional research of individual authors. These papers are not 

meant to represent in any way the views of the U.S. International Trade 

Commission or any of its individual Commissioners. Working papers are 

circulated to promote the active exchange of ideas between USITC Staff and 

recognized experts outside the USITC, and to promote professional 

development of Office staff by encouraging outside professional critique of 

staff research. 

Address correspondence to: 

Office of Economics 

U.S. International Trade Commission 

Washington, DC 20436 USA 

Accounting for Discrepancies in Bilateral Trade: 

The Case of China, Hong Kong, 

and the United States 
Accounting for Discrepancies in Bilateral Trade: 

The Case of China, Hong Kong, and the United States

Michael J. Ferrantino and Zhi Wang 

Office of Economics, U. S. International Trade Commission

April 2007 

ABSTRACT 

China's reported exports to the United States have long been smaller than U.S.-reported 

imports from China. Earlier explanations for this focused on re-exports through Hong Kong, 

and appeared to account for most of the difference. Now, even after taking Hong Kong into 

account properly, there has emerged a new and growing discrepancy which amounted in 

2005 to $46 billion, perhaps 20 percent of the "true" value. Comparisons of detailed customs 

records from China, Hong, Kong, and the United States shows that direct exports from 

Chinese ports and Chinese exports through third countries account for much of the 

discrepancy, relative to trade flows involving Hong Kong. The extent of the problem varies 

markedly across sectors. Some robust correlates for the discrepancy relate to valuation 

issues, U.S. tariffs, and re-exporting through the United States itself. The estimated behavior 

of other potentially important influences is sensitive to the econometric specification 

employed. 

JEL Classification Numbers: F10, F14 

The views expressed in this paper are solely those of the authors, and are not meant to 

represent in any way the views of the U.S. International Trade Commission or any of its 

Commissioners. For assistance with data, the authors thank Jin HongMan and Huang 

Guohua of China Customs; colleagues in the Census and Statistics Department of Hong 

Kong SAR and Eddie Mak at Hong Kong Economic & Trade office in Washington DC; 

Glenn Barresse, Timothy Baxter, and David Dickerson of the U.S. Census Bureau, and 

Shunli Yao for facilitation in obtaining the China Customs data. The authors also would like 

to thank Kyle Caswell and Nick Grossman for their efficient research assistance. 
2

I. Introduction 

It has long been known that the international trade data reported by importers and exporters 

are unlikely to be the same, and in fact may vary greatly from each other for a wide variety of 

reasons. Tsigas, Hertel and Binkley (1992) cite investigations of this question going back to 

the 19th century. By the 1970s, trade discrepancies had already become the focus of national 

and international statistical agencies and economists (U.S. Bureau of the Census (1970), 

Morgenstern (1974), U.N. Economic and Social Council (1974)). Economists working on 

problems for which the data needed to be reconciled have adopted methods for choosing 

either the importer’s or exporter’s data, or some weighted average of the two, as more 

reliable (e.g. Gehlhar (1996), for the GTAP model, and the documentation for Statistics 

Canada’s World Trade Analyzer). 

The standard methods for data reconciliation have generally not worked well for China’s 

trade with the rest of the world. As this trade grew in the 1980s and 1990s, the differences 

between China’s reported trade and comparable data reported by China’s trade partners was 

widely noted. (West (1995), Joint Committee on Commerce and Trade (1996), Fung and 

Lau (1998, 2001, 2003, 2004), Feenstra, Hai, Woo and Yao (1999), Fung, Lao and Xiong 

(2006). For example, in 1991 the United States reported merchandise imports from China of 

$20.3 billion, or over three times as large as China’s reported exports to the United States of 

$6.2 billion.1

 Most of this discrepancy was explained by the large share of China’s trade 

which is re-exported through the customs territory of Hong Kong. In most countries, it is 

believed that in the case of transshipment, the importer’s statistical agencies know more 

about the country of origin than the exporter’s statistical agencies know about the country of 

final destination. Thus, for example, goods which are exported from China to Hong Kong, 

and then to the United States, are likely to be counted in U.S. data as imports from China but 

in China’s data as exports to Hong Kong. Hong Kong’s own data record both an import from 

China and a re-export to the United States. When exports of China and Hong Kong together 

to the United States are compared with U.S. imports from China and Hong Kong together, 

most of the discrepancy disappeared (Figure 1). This was accepted by many researchers as a 

sufficient explanation for the data problem, and led to further inquiries on the special role of 

Hong Kong, in particular the “Hong Kong markup” for goods re-exported through Hong 

Kong (Feenstra and Hanson (2004)). 

 

1

 Both numbers are taken from the IMF’s Direction of Trade data, as reported in Tsao and Whisler (1995). 
3

Figure 1

Eastbound U.S.-China trade 1978-1993

0

10

20

30

40

50

60

1978

1979

1980

1981

1982

1983

1984

1985

1986

1987

1988

1989

1990

1991

1992

1993

Source: IMF Direction of Trade (Tsao and Whisler 

1995)

Billion dollars

U.S. reported imports from

China c.i.f.

China's reported exports to the

United States f.o.b.

U.S. reported imports from

China and Hong Kong c.i.f.

China and Hong Kong reported

exports to the United States

f.o.b.

Average discrepancy index = 

.022

(4.4 percent of average value of 

both reporters - close to a 

possible fob/cif margin)

This paper reports on newly emerging data discrepancies between statistics reported by the 

United States on the one hand, and China and Hong Kong on the other. Even when the role 

of Hong Kong is very carefully accounted for, taking into account transport costs and 

geographical definitions, U.S. reported imports from China and Hong Kong have grown 

persistently larger than the sum of China’s and Hong Kong’s reported exports to the United 

States. (Figure 2) The difference in 2005 is now nearly $46 billion, amounting to about 18 

percent of the reported U.S. number, or about 22 percent of the total figure reported by China 

and Hong Kong together. This discrepancy has grown at the same time that the role of Hong 

Kong as a “middleman” between China and the United States has shrunk. Expressed as a 

share of U.S. reported imports from China, the share of Hong Kong re-exports of goods of 

Chinese origin has declined from about 61 percent in 1995 to about 14 percent in 2006 

(Figure 3). 
4

Figure 2

China-Hong Kong Exports to United States, 1995-2005, with 

corrections for shipping margins and geography

0

50

100

150

200

250

300

1995 1996 1997 1998 1999 2000 2001 2002 2003 2004 2005

billions

US reported imports from

China & Hong Kong (fob)

China & Hong Kong reported

exports to US (fob)

2005 discrepancy index = 

.100

(20.0% of average value of 

both reporters)

2005 difference = $45 8

The newly emerging discrepancy in the data cannot, like the old discrepancy, be explained 

simply by a failure to account for re-exporting through Hong Kong. If it does relate to Hong 

Kong, it must be in a more complex way. It is likely to have other explanations that have 

nothing to do directly with Hong Kong; perhaps more than one explanation, or different 

explanations for different types of products. This paper is dedicated to exploring some 

available explanations for this growing discrepancy. 

The rest of the paper is organized as follows. Section 2 outlines the methodology of our 

inquiry. Section 3 presents the data sources for compiling the mirror statistics of U.S-China 

trade and makes necessary accounting adjustments to estimate the actual size of the statistical 

discrepancy, then compares them with discrepancies between China, Hong Kong and their 

other major trading partners to draw some stylized facts about the discrepancies. Section 4 

provides a more detailed accounting of the discrepancy by subcategories in eastbound trade, 

made possible by direct comparisons of data provided by Chinese, Hong Kong, and U.S. 

primary sources. This allows us, for example, to distinguish between direct exports to China, 

exports through Hong Kong (both re-exports which clear Hong Kong Customs and 

transshipments which do not), domestic exports of Hong Kong, and exports of Chinese origin 

passing through third countries. Section 5 provides an econometric analysis to identify some 

possible factors contributing to the discrepancy, focusing on U.S. imports from China and 

Hong Kong. Section 6 concludes with a discussion of possible directions for future research. 
5

Figure 3.The Declining role of Hong Kong in U.S.-China Merchandise Trade and the 

Widening Discrepancy in Trade Statistics. 

II. Theoretical considerations

2.1 Possible sources of discrepancies in trade data2

Reasons that trade data as reported by exporters and importers may differ from each other 

include, at the very least, the following: 

Timing 

If, for example, a shipment leaves the exporting country in December 2004 and arrives in the 

importing country in January 2005, then one would expect the exporter’s data to be larger in 

2004 and the importer’s data to be larger in 2005. This could be a big problem for monthly 

data, but for annual data the differences in the beginning and end of the year are likely to 

balance out, unless trade is growing very fast and shipping times are long. 

Shipping and insurance costs 

The presence of shipping and insurance costs, which must be added to the value of 

merchandise in order to move it from one place to another, creates a systematic reason for 

import data to be a little larger than export data. Most countries report export data on an f.o.b. 

 

2

 For a further discussion of this topic see Tsigas et al. (1992) and the earlier sources cited therein. 

-10

0

10

20

30

40

50

60

70

80

1995 1996 1997 1998 1999 2000 2001 2002 2003 2004 2005 2006

Hong Kong re-export to US for goods originating from China as % of 

U.S. total imports from China 

Statistical discrepancy as % of U.S total 

import from China and Hong Kong 
6

(free on board) basis, which reflects all costs including loading the good in the exporter’s 

port, or sometimes on an f.a.s. (free alongside ship) basis, which equals f.o.b. minus the costs 

of loading the ship. Import data is usually reported on a c.i.f. (cost, insurance, freight) basis. 

The difference between the f.o.b. and c.i.f. values is known as the f.o.b./c.i.f. margin and is 

usually estimated to equal a few percentage points. If the importing country’s data were 

consistently larger than the partner country’s corresponding export data, but by small 

amounts, we might consider the f.o.b./c.i.f. margin to be the main reason for the difference. 

U.S. import data are somewhat unusual in that the insurance and freight costs are collected 

and reported. This is because the United States assesses duties on the f.o.b. value (known 

officially as “customs value”) rather than on the c.i.f. value, as is the practice in most 

countries. Insurance and freight costs can be measured as the difference between the c.i.f. 

value and the customs value of imports. According to U.S. data, the total f.o.b/c.i.f. margin 

on all imports from China has fluctuated between about 5 and 8 percent of the customs value 

in the last decade, while the margin on imports from Hong Kong has been between about 3 to 

5 percent of customs value. 

General vs. special trade, and goods in transit 

In most countries, trade data often make a distinction between “general” trade data, which is 

meant to represent goods either physically entering or leaving a country, and “special” trade 

data,3

 which are meant to reflect exports actually produced or transformed in a country and 

imports actually consumed. Not all countries use the same practice, and not all users of 

trade data are careful to report which form is being used. Examples of imports included in 

“general” but not “special” trade are imports entered into special warehouses or free trade 

zones, but not clearing customs. Exports included in “general” but not “special” trade consist 

of re-exports of merchandise produced outside of the country and not transformed within the 

country.4

 Although it seems paradoxical, there are cases in which the value of “special” 

imports can exceed those of “general” imports for certain products, because of value added in 

warehouses or foreign trade zones outside the customs territory. 

Even general trade data may not represent all the merchandise which physically enters or 

leaves ports. There is an additional category, known as “goods in transit,” which includes 

merchandise which passes through ports but is not unloaded from the ship or aircraft. Most 

countries have little or no data on goods in transit, though the value of them can be quite 

large for ports like Hong Kong, Singapore, Long Beach or Rotterdam. The possibility exists 

that traders may accidentally (or deliberately) confuse true re-export or transshipment with 

goods in transit. 

 

3

 Singapore Department of Statistics (2005) provides a good discussion of the U.N. standards in this area and 

the differences between national practices. 

4

 The United States maintains both general trade data, known as “general imports” and “total exports,” and 

special trade data, known as “imports for consumption” and “domestic exports.” The difference between total 

exports and domestic exports in U.S. data is called “foreign exports.” 
7

Classification of goods 

Even when the same transaction is reported by both sides, at the same value, the goods may 

be classified differently by the exporter and the importer. This poses problems for users of 

the data who want to identify particular products and industries. Using the Harmonized 

System maintained by the World Customs Organization, goods are classified by type in 

Chapters 1-97. However, countries may use Chapter 98 and, for imports, Chapter 99 to 

identify goods covered by special programs and policies, in which case their classification is 

according to the program or policy. It is not uncommon for one trading partner to record a 

transaction according to the actual type of good (Chapter 1-97) while another trading partner 

records it in Chapter 98 or 99. 

Even when both trading partners try to identify the type of good, they may classify it 

differently, particularly for emerging technologies which have not been assigned a 

classification, or for which the classification is ambiguous. Examples of such goods are fuel 

cells, and devices which serve simultaneously as photocopiers, printers, and fax machines. 

Re-export 

Re-export takes place when goods enter into a customs territory from one country and are 

shipped to another country without being transformed. Re-export is a growing phenomenon 

in the world economy.5

 More than 90 percent of Hong Kong’s total exports now represent 

re-exports either from China or from a third economy, up from less than 30 percent in the late 

1970s. More than 10 percent of U.S. total exports now represent re-exports. The term 

“transshipment” should be interpreted with caution. It is often used as a synonym for “reexport”, but can also mean “goods in transit” as defined above, depending on the context. 

The practice of re-exporting gives rise to a wide variety of possibilities either for the origin or 

the final destination of commodities to become confused. This is particularly troublesome 

when policymakers desire to see statistics on the “special” basis, where exports represent 

national production and imports represent what has been entered into national markets for 

consumption. If a shipment goes from A to B to C, we usually think of A as the “true” origin 

and C as the “true” destination, but country A could easily record its exports as going to the 

country of shipment (B) rather than the final destination C, while country C could record its 

imports as coming from the country of shipment (B) rather than the ultimate origin A. 

It is usually thought that the importer is more likely to know the ultimate origin than the 

exporter is likely to know the ultimate destination, particularly if a “middleman” in B decides 

where the product will ultimately be shipped to. If this is true, then the importer’s data are 

likely to be larger. As we saw above, recognizing that Hong Kong acts as such a middleman 

was enough to produce a good reconciliation of U.S. and Chinese trade data through about 

the mid-1990s. However, this rule of thumb may not always hold, and there may be certain 

 

5

 See Andriamananjara, Arce, and Ferrantino (2004). 
8

types of transactions for which the exporter knows more about the final destination than the 

importer knows about the ultimate origin. In this case, the exporter’s data would likely be 

larger. 

The phenomenon of goods in transit can potentially give rise to problems similar to those 

caused by re-export, as can confusion between true re-export (when the goods actually enter 

the customs territory in B) and transit (when the goods simply pass through the port without 

clearing customs). 

Fung and Lau (2003) noted that “some Chinese exports to Central and South America, 

including the Caribbean countries, have been routed through U.S. ports such as Los Angeles 

and Miami. There is a question of whether these exports may have been included in the U.S. 

trade statistics as Chinese exports to the United States.” 

Differences in recording re-exports between countries also provide challenges. For many 

large traders, including Japan and most of the European Union, re-export data are not readily 

available. The United States has detailed re-export data, but only records the country of 

destination, rather than the country of origin. Hong Kong’s data make it possible to identify 

both sides of a re-export transaction. However, even Hong Kong’s re-export statistics may 

not fully capture the complexity of shipments that pass through its ports. 

Some of the challenges of reconciling Hong Kong data to China and U.S. data are illustrated 

in Tables 1 and 2. Table 1 provides an attempted reconciliation of the bilateral trade between 

China and Hong Kong, as reported by the two customs authorities, while Table 2 gives some 

data on trade and cargo shipping with the United States, as reported by China’s and Hong 

Kong’s customs authorities. There are four types of shipment are classified by Hong Kong 

Census and Statistics Department: imports, exports (including domestic exports and reexports), inward transshipment, and outward transshipment. Goods imported into or exported 

from Hong Kong are classified as direct shipment, while goods transshipped in Hong Kong 

under a through bill of lading are classified as transshipment. This refers to cargo that is 

consigned from a place outside Hong Kong to another place outside Hong Kong but is or is 

to be removed from one vessel and either returned to the same vessel or transferred to 

another vessel within Hong Kong waters6

. It is different with goods imported into Hong 

Kong for subsequent re-exports and usually do not go through Hong Kong custom valuations. 

This means a large portion of China’s exports via Hong Kong to the world may be only 

transferred through Hong Kong and do not reflect in Hong Kong re-export statistics. Section 

A in Table 1 compares trade statistics reported by China and Hong Kong with Hong Kong’s 

“Port Cargo Discharged by Major Country/Territory and Port of Loading” statistics, it shows 

that as the difference between China reported exports via Hong Kong (but Hong Kong may 

be or may not be the final destination) and Hong Kong reported imports from China increase, 

the inward transshipment from China as percent of Hong Kong’s total cargo shipment 

received from China also increase. The similar correlation also can be found from the 

statistics of China and Hong Kong export to the United States and Hong Kong’s outward 

transshipment to the United States as percent of Hong Kong’s total shipment to the United 

States (Section a of Table 2). 

 

6

 Definition provide by Hong Kong Census and Statistical Department.
9

Section B of Table 1 compares trade statistics reported by China and Hong Kong with Hong 

Kong’s “Port Cargo Loaded by Major Country/Territory and Port of discharge” statistics, it 

shows that as the difference between China reported imports through Hong Kong (but Hong 

Kong may be or may not be the country of origin) and Hong Kong reported exports to China 

increase, Hong Kong outward transshipment to China as percent of Hong Kong’s total 

shipment to China also increase. The similar correlation also can be found from the statistics 

of China and Hong Kong import from the United States and Hong Kong’s inward 

transshipment for the United States as percent of Hong Kong’s total shipment received from 

the United States (section B Table 2). 

It is very possible that in China’s customs statistics, exports via Hong Kong may include part 

of re-exports through Hong Kong and part of transshipment through Hong Kong. However, 

this is very difficult to confirm empirically, since re-exports are measured in dollars and 

transshipments in tons in Hong Kong’s trade and cargo shipment statistics, it is difficult to 

directly compare the one with the other. A proper way to measure China’s transshipment 

through Hong Kong and its relation with direct exports and imports reported by China 

Customs is needed to fully understand the observed discrepancy in trade statistics reported by 

both sides. The unpublished U.S. shipping statistics may provide additional information in 

this regard and this area needs to be examined further. 

Partner country attribution and treatment of processing trade 

Attribution of imports to country of origin and exports to country of destination often explain 

many significant differences when goods move from the country of origin to the country of 

destination via a third location in international trade statistics. In the case of Chinese exports, 

the country of final destination may not know at the time of exports, and the status of Hong 

Kong as a free ports increase the incentive for exporter to declare their merchandise are for 

home use in Hong Kong , even the goods actually is used for re-exports. The large portion of 

Chinese exports belongs to processing parts and components, making the attribution of 

country of origin more complex, however, without discuss the differences of partner country 

attribution and treatment of processing trade between the U.S. and Chinese statistical system 

to recording merchandise trade, we can not see the logical link between processing trade and 

statistical discrepancies, 7

 because the discrepancy we discussed here treat China and Hong 

Kong as one side of the mirror, as a results, the difference between statistics from China and 

Hong Kong become less relevant. 

Mis-invoicing, transfer pricing, and mis-attribution 

 

7

 A recent presentation made by China’s Statistics Department of Customs General 

Administration, conclude that “despite the decreasing trend in reliance on Hong Kong in 

(China’s external trade), the increasing scale of the processing trade means large 

discrepancies will still exist in the future” (Hongman Jin, “Reasons for Discrepancies in China’s 

External Trade Statistics with partners: the Particular Role of Processing Trade”, 6th OECD International 

Trade Statistics Expert Meeting, Statistics Directorate, September, 2005 

http://www.oecd.org/dataoecd/51/6/35308958.pdf ) 
10

Mis-invoicing (under invoicing and over invoicing) involves declaring the value of goods to 

be either higher or lower than their true value. Mis-attribution takes place when traders 

deliberately make false declarations about the origin or destination of a good. Incentives for 

mis-invoicing may include tax evasion, tariff evasion, and circumvention of a quota or tariffrate quota. For example, if tariffs are high there is an incentive for the exporter to underinvoice the good. The incentives for mis-attribution could include taking advantage of 

special programs which provide duty reductions or drawbacks. For example, imports into the 

United States from outside NAFTA might be misattributed as being imports from Canada or 

Mexico. Firms that wish to take advantage of China’s processing trade programs must 

identify certain imports into China as being intended for use in producing Chinese exports, 

while firms using the provisions of U.S. Section 9802 must identify certain U.S. exports as 

being intended to be processed outside the United States and returned as U.S. imports. False 

declarations to take advantage of such programs could lead to both mis-valuation and 

geographical mis-attribution. 

Transfer pricing refers to mis-invoicing engaged in by related parties in different countries, 

such as different branches of a multinational corporation. By under- or over-invoicing, firms 

can shift profits from high-tax countries to low-tax countries, as well as avoid tariffs.8

 The 

incentives to do this are particularly strong when firms ship to themselves specialized “firmspecific” components or intermediate goods for which there is no obvious market equivalent 

to establish an “arms’ length” price. On the other hand, the practice of transfer pricing is 

limited both by the fact that keeping “two sets of books” may impede the firm’s ability to 

monitor its own operations and by the fact that national tax authorities have some 

enforcement powers to prevent abuses of transfer pricing. The role of Hong Kong, which is 

both a duty-free customs area and a low-tax location, in U.S.-China trade suggests that the 

incentives for mis-invoicing and mis-attribution may be particularly high.9

Smuggling 

Smuggling may be treated conceptually as the most extreme case of under-invoicing; the 

transaction is not recorded at all, so its value is zero. Situations which provide incentives for 

under-invoicing also provide incentives for smuggling, particularly if the incentives are large. 

Particular incentives for smuggling exist if either exports or imports of a commodity are 

illegal (e.g. for certain drugs, explosives, weapons, pornography, endangered species, etc., or 

for goods which otherwise would be legal except for intellectual property violations.) 

Smuggling can lead to discrepancies in trade statistics if goods which are legal to export (or 

import) in one partner are illegal in the other partner, if the degree of enforcement is different 

in the exporting and importing countries, or if smugglers engage in misattribution of origin or 

destination. 

It may be the case that even large volumes of smuggling could take place without leaving any 

visible discrepancy in official trade statistics. This could take place if the smuggling activity 

produces neither an export record nor an import record. 

 

8

 See Bernard, Jensen, and Schott (2006) for a recent study of transfer pricing by U.S.-based multinational firms. 9

 See in particular Fisman, Moustakerski, and Wei (2004) on the potential role of tariff evasion in trade 

involving Hong Kong. 
11

2.2 Measuring discrepancies among the trade statistics of China, Hong Kong and the 

United States 

Trade data reported by each country and its partners are often used in international economic 

literature to check the quality of trade statistics. Theoretically, export statistics from one 

country to its partner countries should match the import statistics from their partner countries. 

This often refers to as mirror statistics. An approximate match of mirror statistics implies 

trade data reported via that routine are reliable. However, discrepancies always occur for 

many reasons as discussed in previous section. 

Mirror statistics is used as the basis to calculate the magnitude of statistical discrepancy in 

this paper. However, there is an import aspect the methodology used here differs from 

methodologies used in previous studies. We compile the mirror statistics by treating data 

reported by China and Hong Kong as one side of the mirror and data reported by the United 

Sates as the other side.10 Because U.S. records imports based on country of origin according 

to UN guidelines, its reported imports from China include goods directly shipped from China 

and indirect shipped from Hong Kong and other countries, while U.S. reported imports from 

Hong Kong only include good originated from Hong Kong11. Therefore, in eastbound trade, 

the exports side of the mirror should equal China’s reported exports to the United States, plus 

Hong Kong domestic exports and Hong Kong reported re-exports for China to the United 

States, while import side of the mirror should equal the sum of U.S. reported total imports 

from China and Hong Kong. Similarly, in westbound trade, the exports side the mirror 

should equal U.S. reported exports to China, plus U.S. reported total exports to Hong Kong, 

while import side of the mirror should equal the sum of China and Hong Kong reported 

imports originated from U.S. after fob/cif adjustment minus Hong Kong re-exports for the 

U.S. to China, because U.S indirect exports to China through Hong Kong will be counted 

twice in the sum of China and Hong Kong reported imports: once when it enters Hong Kong 

Customs, then counted again by China’ Customs when it is re-exported to China. It implies 

both China and Hong Kong also records imports based on country of origin according to UN 

guidelines similar to the United States. The advantage of doing this is it simplifies the 

estimation of actual statistical discrepancies by avoiding adjust Hong Kong re-export markup 

first, which often varies widely (Feenstra and Hanson, 2004)12, depending on the source data 

and methodology. In other words, the actual size of statistical discrepancies calculated by this 

method will free from the complication of the error generated by the estimation of Hong 

Kong’s re-export markup, thus statistically more desirable. The mirror relation of the 

 

10There are many good reasons treat trade statistics from Hong Kong separately besides it is a separate customs 

territory. For instance, there have historically been significant amount textile quotas allocated to Hong Kong. 

11 In general, for nonpreferential trade the United States considers the country of origin to be the last country 

where a “substantial tansformation” took place, regardless of the portion of the final import value of the product 

that is added by processing that takes place in other countries after the “substantial transformation.” 

International Economic Review, United States International Trade Commission, Oct./Nov., 1996, p. 13. 12 In this paper, Feenstra and Hanson reported Hong Kong’s re-export markup has a mean of 0.375 with a 

standard error of 0.358 based on official data from China and Hong Kong at 4 digit SITC level covering period 

1988-1998. They also report the presence of negative markups are a genuine feature of their data, similar with 

what find by Feenstra et.al (1999) in China-US westbound trade. 
12

reported trade statistics in both directions is depicted in Figure 4a and 4b. For a complete 

consistent accounting relation between China, Hong Kong and their trading partner reported 

trade statistics, please refer to (Wang, Gehlhar and Yao, 2006). 

After properly identifying the two sides of mirror statistics in US-China trade, three measures 

of statistical discrepancy can be defined. The first one measures the discrepancies at 

commodity level for each trading partner:13

(1) 

 

where M is partner r reported imports of commodity i from country s at year t, E is reporting 

country s reported exports of commodity i to partner r at year t. This index always measures 

discrepancies between the two sides of mirrored trade statistics as a percent of reported 

import flows. 

The second index uses the sum of the two partner reported data as the denominator,14 It 

varies between -100 (M=0, E≠0) and 100 (M≠0, E=0). When the two reported statistics are 

not far away, the numeric value of the two measures should be very close to each other. 

 

(2) 

In eastbound trade, E equals the sum of China reported exports to partners, Hong Kong 

reported domestic exports to partners, and Hong Kong reported re-exports for China to 

partners; M equals the sum of partner reported imports from China and Hong Kong. In 

westbound trade, E equals the sum of partner reported exports to China and Hong Kong, 

while M equals the sum of China and Hong Kong reported imports from partner minus Hong 

Kong reported re-exports for partner to China.

 

13 There is a consensus in trade statistics reconciliation work to use import data as a benchmark for comparison 

of most commodities. Import data usually are considered to be more reliable than export data because imports 

have to be reported in sufficient details to allow Customs to apply tariffs, taxes, trade agreements or other 

regulatory controls. For the same reason, Customs offices generally more attentive to goods entering the 

country as opposed leaving the country. Therefore, for those countries consistently report exports higher than its 

partners’ imports, there may be double counting involved. 

14 This index is due to Austin Barron of American University (International Trade Centre (2005)). A similar 

index can be constructed using the mean of the importers’ and exporters’ data (M + E)/2 as the denominator, 

rather than the sum. If the mean is taken as a first estimate of the true value (or put differently, if the values of 

the ER index are multiplied by 2) this produces an index which is more directly comparable to DIF. 

sr Mit

sr

it E sr Mit DIFsr

it

− =100

( )

200

0.5( )

100

sr

it E sr Mit

sr

it E sr Mit

sr

it E sr Mit

sr

it E sr Mit ERsr

it

+

− =

+

− =
13

Figure 4a Mirror Relation among China, Hong Kong and US Officially Reported Trade 

Statistics - Eastbound Flows

China reported 

total exports 

to U.S. (fob)

+ Hong Kong 

reported domestic 

exports to U.S. (fob)

Hong Kong Reported 

re-exports of China 

originated 

goods to U.S. (fob)

China indirect 

Export to U.S. 

via Hong Kong

Hong Kong’s 

markup for re-export 

China originated 

goods to U.S

U.S. reported 

imports originated 

from China (fob)

U.S. reported 

imports originated + from Hong Kong (fob)

=

Figure 4b Mirror Relation among U.S., China and Hong Kong Reported Trade 

Statistics - Westbound Flows 

U.S. reported 

total exports 

to China (fas)

U.S. Reported

Total exports to 

Hong Kong (fas)

Hong Kong Reported 

Total re-exports of U.S 

originated goods 

U.S. indirect 

exports to China 

via Hong Kong 

Hong Kong’s 

reported re-export 

U.S. originated goods 

to other countries

China reported 

imports of U.S. 

originated 

prodicts (cif)

Hong Kong reported 

imports of U.S 

originated 

products (cif)

+

+

fob/cif

adj

fob/cif

- adj -

-
14

The third measures are absolute average aggregation index by partners or by commodities 

from the second one, and defined as follows: 

 (3) 

Where 

(4) 

Where 

The two indexes vary between 0 to 200. The lower the value of the indexes, the smaller the 

size of the discrepancies, the higher and the degree of consistency for the mirror trade 

statistics. 

III. Stylized facts from the data 

3.1 Data sources 

We obtained China reported trade statistics at the most detailed HS level (8 digit) from 

Customs General Administration of China, Hong Kong reported trade and re-export statistics 

(8 digit HS) from Census and Statistical Department of Hong Kong, and U.S. reported data 

(6 digit HS) from USITC’s Oracle database. All data cover 12 years from 1995 to 2006. To 

check whether the pattern of statistical discrepancies between trade data reported by China 

and Hong Kong with the United States are different from discrepancies with their other 

trading partners, we also download trade data at 6 digit HS from the United Nation 

COMTRADE database for about 150 reporting countries from 1995 to 2004, to compile the 

mirror statistics and calculate the discrepancy measures for China and Hong Kong with all 

their major trading partners in a similar way. 

Before we calculate the discrepancy measures according equations (1) to (3) based on mirror 

trade statistics from official data sources, three adjustments are made to bring statistics from 

both sides comparable: 

a. Geographical coverage difference: The United States includes Puerto Rico and the U.S. 

Virgin Islands as part of its statistical territory while China and Hong Kong treats them as 

| | sr

it ER srit AER i w sr

t = ∑

∑ +

+ =

i

sr

it E sr Mit

sr

it E sr

sr Mit

it w

( )

∑ +

+ =

r

sr

it E sr Mit

sr

it E sr

sr Mit

it S

( )

| | sr

it ER srit s r AERs

it = ∑
15

separate jurisdictions. To make the mirror statistics comparable, exports to and imports 

from Puerto Rico and the U.S. Virgin Islands are subtracted from U.S reported statistics 

based on data from U.S. Census; 

b. Classification coverage difference (treatment of HS 98 and 99). The U.S. includes certain 

special programs and transactions in HS Chapter 98 & 99. These are not directly comparable 

to China’s or Hong Kong’s data, which may record the same goods in HS 1-97 or exclude 

them altogether for their data. Thus, data for HS 98 and 99 are omitted in the comparison. 

 

c. Valuation difference: in westbound trade, China and Hong Kong values its imports on a 

c.i.f. (cost, insurance, freight) basis, while the United States values its exports on an f.a.s. 

(free alongside ship) basis that does not include shipping costs, therefore, adjustments are 

made based on 60 percent of actual f.o.b./c.i.f. ratio calculated from detail U.S. import data, 

based on transportation cost is much lower for goods shipped westbound than eastbound.15 

However, in the eastbound trade, U.S. Census reports import as general customs value, 

along with custom duty collected and cost of insurance and freight. The former by definition 

is “value of the imports, as appraised by U.S. Customs, excluding U.S. imports duties, freight, 

insurance, and other charges incurred in bringing the merchandise to the U.S. for General 

Imports”, which is equivalent to the fob value, therefore, no c.i.f. to f.o.b. adjustment need to 

be made. 

3.2 Eastbound trade16

Table 3 presents the official mirror statistics of China’s and Hong Kong’s exports to the 

United States, related adjustments, and resulted estimates of statistical discrepancies during 

1995 to 2006. It starts from U.S. officially reported merchandise imports from China and 

Hong Kong, adjusts by geographic coverage difference, plus the statistical discrepancies and 

finally arrive at China and Hong Kong officially reported exports (include Hong Kong 

reported re-exports of China originated good to the United Sates) covering the same period. 

There are four interesting observations. First, China and Hong reported more exports to the 

United States than U.S. reported imports during 1995 and 1996 and reached a roughly 

consistence in 1997. The discrepancy increase rapidly since then and reached its peak at 

nearly 20 percent in 2004. From 1998 to 2006, the difference between China reported exports 

to the United States and U.S. reported its imports from China more than doubled. Second, 

the role of Hong Kong in intermediating China’s exports to U.S. market decline rapidly in 

last decade, from more than 60 percent to about 14 percent, while share of China originated 

 

15 This is approximately the ratio found in a sample of comparable westbound to eastbound rates between China 

and the United States obtained from the Maersk shipping company (http://www.maerskline.com). The 

economic incentives for such a difference in rates arise from China’s bilateral surplus with the United States; it 

costs more to reserve space on a full eastbound container going, e.g. from Shanghai or Hong Kong to Los 

Angeles than to get the same space on a more-empty westbound container on the same route. 16 The measured discrepancy on the westbound trade (exports of the United States to China plus Hong Kong) is 

a good deal smaller than on the eastbound trade and shows no apparent trend. Discrepancies of China-Hong 

Kong trade data with those of trading partners other than the United States show substantial variation and can be 

of either sign. While the full analysis of these trade flows exceeds the scope of the present paper, relevant 

summary statistics are available from the authors on request. 
16

goods in Hong Kong total re-exports to the US stay constant at more than 90 percent. Third, 

Hong Kong’s domestic exports to the United States decline consistently, re-exports of 

Chinese made products consisted more than 80 percent of its gross exports to the United 

States since 2002 and this trend probably will continue in the coming years, as Hong Kong’s 

economy become more and more service-oriented. Finally, the geographical coverage 

adjustment were small relative to the remaining unexplained statistical discrepancies, 

indicating there are other important contributing factors besides Hong Kong’s re-export 

activities need further exploration. 

Look at the computed discrepancies index for major HS sections reported in Table 4, textile 

(HS chapter 51-63) seems to be the best matched mirror trade statistics between China and 

Hong Kong reported exports and U.S. reported imports, largely due to the quota system in 

place that provides sufficient incentives for both sides to precisely record the trade flows. 

Arms and ammunition (HS chapter 93) and works of art, collections’ pieces and antiques (HS 

chapter 97) are the two major HS sections with consistently under reported exports by China 

and Hong Kong during the 12 year period (U.S. reported imports is more than two times of 

China & Hong Kong reported exports in most years); while vehicles, other transport 

equipment and their parts (HS chapter 86-89) and beverages and tobacco (HS chapter 16-24) 

are the two major HS sections that China & Hong Kong reported exports consistently 

exceeds U.S. reported imports. This may imply that under-invoicing behavior is a common 

practice for certain commodities in eastbound trade, however, whether under-invoice 

happens at the point of exports or imports depends on the specific characters of the traded 

products. For instance when Chinese exporters export art work and antiques, they usually 

intend to under-value the commodity, while when U.S. importer imports tobacco products 

from China, they may intentionally under report the value of their imports (smuggling ?) for 

tariff evasion purpose. In the meantime, over-invoice behavior also could happen, for 

example, when Chinese exporter exports auto parts to the United States, the may over-value 

their exports for export tax rebate purpose. 

In order to see whether the rapid growing statistical discrepancies are unique features 

between China and Hong’s exports to the United States and U.S. reported imports, we further 

compile mirror statistics in a similar way for their exports to their other major trade partners 

using data from UN COMTRADE database and compute three indexes of statistical 

discrepancy. The results for China’s top exporting counties are listed in Table 5.17 Those 

indexes reveal that there are only two countries (Japan and Korea), among China’s major 

trading partners, reported imports matched closely with China and Hong Kong reported 

exports (The discrepancy as % of partners reported imports was consistently less than 10 

percent in the ten year period). While other partner countries can be classified into two 

groups according to the sign of the statistical discrepancies. The first group is characterized 

by increasing positive discrepancies over the 10 year period as the United States, while the 

second group all has a negative, although diminishing, discrepancy during the same period, 

implying their reported imports from China and Hong Kong were consistently lower than 

 

17 Because we did not have fob/cif ratio for China and Hong Kong’s trade with most their trading 

partners except the United States, all imports are valued at cif price in this calculation. A less than 10 

percent positive discrepancy in the compiled mirror trade statistics indicates a close match of the 

reported trade data. 
17

what China and Hong Kong reported exports to them. The first group includes all the 

countries in North American, most countries in Europe, Australia and New Zealand, 

Argentina, Malaysia, Thailand and Indian. The second group includes Taiwan, Russia, Chile 

and most of the large developing countries such as Indonesia, Philippines, Brazil, Saudi 

Arabia, and South Africa. The aggregation of all other smaller reporting countries also fell 

into this group. Aggregate all reporting partners, the discrepancy increase from less than 

negative 1 percent in 1995 to over 18 percent in 2004, quite consistent with the growing 

pattern of discrepancies in the mirror statistics of U.S.-China eastbound trade. 

3.3 Westbound trade 

Table 6 presents the official mirror statistics of China’s and Hong Kong’s imports from the 

United States, related adjustments, and resulted estimates of statistical discrepancy from 

1995 to 2006. It starts from U.S. officially reported merchandise exports to China and Hong 

Kong, deduct geographical coverage difference from U.S. reported data, plus fob/cif margin, 

Hong Kong reported re-exports U.S. originated goods to China, and a statistical 

discrepancies, finally arrive at China and Hong Kong published imports from the United 

States covering the same period. 

Different from the east bound data, there seems no obvious pattern in the aggregate statistical 

discrepancy during the 12 year period. However, Hong Kong and China reported imports 

from the United States slightly exceeded U.S reported exports to China and Hong Kong only 

in two of the twelve years (1999, 2004), export side of the mirror statistics are larger than the 

import side in a relatively large magnitude for rest the ten years. This suggests underinvoicing of Chinese imports from the United States for the purpose of tariff evasion and 

other incentive reasons seems more common and dominated more sectors in westbound trade 

than eastbound trade, a similar funding to Fung, Lau and Xiong (2005). Other notable 

features of the data are the decline role of Hong Kong in facilitating U.S. exports to China. 

Hong Kong re-exports for U.S. originated goods as percent of total China imports from the 

United States has declined from over 30 percent in 1995 to about 12 percent in 2005. In the 

meantime, U.S. share in total Hong Kong re-exports to China for all countries declined from 

more than 10 percent in 1995 to less than 5 percent in 2005. 

Look at the computed discrepancies index for major HS sections reported in Table 7, the 

most consistently under-reported China & Hong Kong imports is arms and ammunition (HS 

chapter 93)18, followed by miscellaneous manufactured products (HS chapter 94-96), 

precious stones and metals (HS chapter 71), while only two of the 22 major HS sections, 

paper & paperboard products (HS chapter 47-49), and instruments, clock & watches (HS 

chapter 90-92), China & Hong Kong reported imports are consistently exceeded U.S. 

reported exports. However, at the aggregate level, the magnitude of discrepancies between 

China & Hong Kong’s imports and U.S. reported exports is much smaller than the 

discrepancies in eastbound mirror trade statistics, implies possible classification 

inconsistence problems between the two traded sides. 

 

18 Based on Statistical department of China’s Custom Administration, arm imports and exports are 

reclassified into Chapter 98. 
18

To put the statistical discrepancy of U.S-China westbound trade in perspective and check 

whether under-invoice is a common feature of China’s imports, we also compiled mirror 

statistics for imports of China and Hong Kong from their other major trading partners using 

data from UNCOMTRADE, estimate the three indexes of statistical discrepancy similar to 

what we did in eastbound trade. The results are listed in Table 8. 

Similar to China-US west bound trade, seems there are consistent under invoice for China’s 

imports, especially before 200019. Most major trading partners reported exports consistently 

larger than China and Hong Kong reported imports from them. Singapore and Israel, in 

particular, reported exports significantly higher than China and Hong Kong reported imports 

during the whole period. The pattern of discrepancies is quite similar for EU15, Japan and 

the United State, and the magnitude is relatively small, indicating the quality of data reported 

in those routines are relatively better than other routines. Particular large positive 

discrepancies appear with some large developing countries, such as Mexico, Saudi Arabia, 

South Africa, Russia, Philippines and other reporting partner countries, while the magnitude 

of discrepancies is much smaller when aggregate across all partners, implying misreported 

country of origin for Chinese imports may be also one of the major causes of the 

inconsistencies between China & Hong Kong reported imports and partner country reported 

exports. 

In both direction of trade flows, some of the estimated discrepancies with partner reported 

trade data may be easy to explain such as with Netherlands (transshipped to other EU 

countries) and Panama (a large portion of China’s export there may actually went to the 

United States), because they are also world center of entrepôt trade. But with many of the 

other partners may be caused by very different reasons such as smuggling (Russia and some 

large developing countries), under-invoice (incentives in particular sectors), therefore, further 

decomposition of the overall discrepancies into their sources at data collection is in order, 

which may provide some useful hints to identify the major factors underlying the growing 

discrepancies. 

IV. Decomposition of eastbound discrepancies by subcategories of flows 

In Chinese export statistics, China Customs asks traders to declare both a “country of 

departure”, which refers to the next stop exported goods arrive at after they depart a Chinese 

port (not necessarily the final destination country), and “countries of consumption”, which

refers to the final destination country where goods will be consumed. Based on such 

information, China’s exports to the United States can be subdivided into three categories: 

 

a. The United States is both “country of departure” and “country of consumption.” 

These represent direct exports from China to the United States, e.g. shipments which 

travel non-stop from Shanghai to San Francisco;

 

19 Please note the import data used here to calculate the measure of discrepancies are valued at cif 

price, which is different with the data used in calculating the measure of discrepancies with the 

United States reported in tables 6 and 7, therefore, a 5% or less positive discrepancy in the compiled 

mirror trade statistics still indicates China & Hong Kong reported imports is less than partner reported 

exports. 
19

b. The “country of departure” is Hong Kong but “country of consumption” is the 

United States, which is product shipped to the United States via Hong Kong;

c. The “country of departure” is a third country other than Hong Kong, and the “country 

of consumption” is the United States. 

As has already been mentioned, Hong Kong’s statistical authority reports both Hong Kong’s 

domestic exports (goods made in Hong Kong) and Hong Kong re-exports for other countries, 

which refers to products which clear Hong Kong customs as imports and are then re-exported. 

These products undergo Hong Kong Customs valuation twice, at the time of importing and at 

the time of re-exporting, with the difference in valuation being the “Hong Kong markup.” In 

the case of transshipments through Hong Kong (goods passing through Hong Kong ports 

without clearing Customs), only weight data are reported, not value, so that Hong Kong data 

on transshipment is reported in the aggregate, in metric tons, with no commodity breakdowns. 

There is a question as to whether category b. in China Customs data reflects re-exports 

through Hong Kong (goods passing through Hong Kong Customs) or transshipment (goods 

passing through Hong Kong ports but not through Customs). The most straightforward 

interpretation is that category b reflects transshipments. This is because the “country of 

consumption” in most cases will be the same as the first country where the products clear 

customs, and thus re-exports would be recorded in Chinese data as exports to Hong Kong as 

country of consumption, rather than exports to the United States. These are the transactions 

that have traditionally been assigned the leading role in the discrepancy. Since the goods 

usually are handled by a Hong Kong middleman, the Chinese exporter may not in fact know 

the final destination. If the exporter in fact knows that the final destination is the United 

States, but the shipment passes through Hong Kong for logistical reasons, it is more likely to 

have a through bill (i.e. be a transshipment) in order to avoid the trouble and expense of 

clearing Hong Kong customs. However, this interpretation may not always be reliable. If 

some Chinese exporters may confuse the categories of re-export and transshipment through 

Hong Kong in their reporting, so that some re-exports may in fact generate type b statistical 

records. As we shall see, there are some features of the data that lend credence to this 

possibility. 

In summary, we identify five possible trade flows in the data from China and Hong Kong 

Customs and designate them as follows: 

C1. China’s direct exports to the United States; 

C2. China’s reported exports to the United States via Hong Kong;

C3. China’s reported exports to the United States via third counties other than Hong 

Kong (C1-C3 correspond to a – c above);

C4. Hong Kong’s reported domestic exports to the United States; and

C5. Hong Kong’s reported re-exports of goods of Chinese origin to the United States.

As we discussed earlier, based on U.N, guidelines, U.S. reported imports from China include 

goods of Chinese origin, whether directly shipped from China or indirectly shipped from 

Hong Kong and other countries, while U.S. reported imports from Hong Kong only include 

goods originated from Hong Kong. Official U.S. trade data as reported only identify 
20

countries of origin. However, the detailed U.S. import records we have obtained from U.S. 

Census, which cover all U.S. imports from China during 1995-2005, allow us to identify 

ports of shipment, as well as whether the goods entered into commerce (cleared customs) in a 

third country en route to the United States. Supplementing these with the publicly reported 

official data on U.S. imports from Hong Kong, we can identify the following five categories 

in U.S. data: 

 

U1. Shipment to the United States directly from ports within China; 

U2. Shipments to the United States from China, but last port of departure is Hong 

Kong, and the goods did not enter into commerce in Hong Kong (Hong Kong 

transshipment); 

U3. Shipment to the United States from China, but the last port is in a third country 

other than Hong Kong; 

U4. U.S. imports of Hong Kong origin (from the official published data); 

U5. Shipment to the United States from China of goods which have entered 

commerce in Hong Kong and for which the last port of departure is Hong Kong, i.e. 

Hong Kong re-exports. 

 

Adopting the simplest interpretation of C2 above, there is a one-to-one correspondence 

between C1-C5 and U1-U5 in that order, which yields five mirrored relationships as 

portrayed in figure 5. 

 

There are two additional boxes in the figure. The grey box with a question mark indicates 

transshipment through Hong Kong as reported in the Hong Kong cargo data. As noted above, 

since these data are only available in tons rather than in values and are not identified by 

commodity, they cannot be easily entered into the analysis. The black box with a question 

mark represents goods of Chinese origin re-exported through third countries. If we interpret 

C3 as being transshipment only and U3 as including both transshipment and re-export, then 

there is potentially a missing piece (re-exports by third countries other than Hong Kong) as 

represented by the black box. 

Tables 9 and 10 contain an analysis of the data as per the five-way mirror. Of the total 

discrepancy in 2005, amounting to $46.3 billion, $36.5 billion, or 79.9 percent of the total, 

consists of the discrepancy for direct trade from China to the United States.20 This compares 

with a share of direct trade in the total China-Hong Kong exports to the United States of 68.5 

percent (according to China-Hong Kong data) or 70.6 percent (as per U.S. data), indicating 

that the degree of underreporting in China-Hong Kong export records (or over reporting in 

U.S. import records) is above-average. 

 

20 In US shipping data, direct imports from China can be further break down into three parts: 1. Shipment to US 

from a know ports within China; 2. The goods enter commerce in China, shipped from an unknown ports 

believed within China, and 3. US imports shipped from an unknown country, and the last ports before the goods 

shipped to US is a ports outside China, but for some reasons, US custom classified the imports is from China. 
21

Figure 5 Mirror Relation among China and Hong Kong Officially Reported Trade 

Statistics and U.S Unpublished Shipping Data - Eastbound Flows

The discrepancy in trade passing through countries other than Hong Kong is very large. In 

2005, imports from China passing through third countries reached $11.1 billion per the U.S. 

Census data, over 20 times larger than the $459 million reported by China Customs. It is the 

second-largest source of the discrepancy in dollar terms, accounting for 23.0 percent of the 

discrepancy as compared to only 4.4 percent of the imports, using U.S. data. This is in part 

explained by the usual asymmetry in information between importers and exporters, with 

importers knowing more about ultimate origins than exporters about final destinations. 

Moreover, China’s relations with third-party reporters other than Hong Kong are likely to be 

weaker than those with Hong Kong. 

The data in Table 9 also show that the three types of Hong-Kong based transactions as a 

group account for a smaller share of the discrepancy than they do of the total trade. Using 

U.S. data as the denominator, the three Hong Kong related trade flows account for 25.1 

percent of U.S. imports from China-Hong Kong in 2005 but only a small and in fact negative 

discrepancy (-$362 million, or 0.5 percent of the total.) Concealed within this total are 

several larger discrepancies. U.S.-reported imports of Hong Kong domestic goods are almost 

twice those reported by the Hong Kong authorities. The large negative value of the 

discrepancy in transshipments more than offsets the positive discrepancy in re-exports. This 

may be indirect evidence for the hypothesis advanced above that some exports reported to 

China Customs as “via Hong Kong” may in fact represent re-exports rather than 

transshipments. 

C1. China 

reported direct 

exports to the 

U.S. (fob) 

C4. Hong Kong 

reported domestic 

exports to the United States 

(fob) C2. China reported 

exports to U.S. via 

Hong Kong (fob) 

C3. China reported 

exports to the U.S.. via 

third countries (fob) 

C5. Hong Kong reported 

re-exports of China 

originated goods to US (fob)

Hong Kong reported 

transshipment of 

China originated goods 

to U.S. in metric tons

U1. U.S. imports shipped 

directly from ports 

within China (fob) 

U5. U.S. imports shipped 

From Hong Kong ports 

as re-exports for 

 China (fob) 

U2. U.S. imports shipped 

from Hong Kong ports 

as transshipment for 

 China (fob) 

U3. U.S. imports China 

Originated goods shipped 

from third country ports 

(fob) 

U4. U.S. reported 

imports from 

Hong Kong (fob) 

Third Country 

 reported re-export 

 of China originated 

goods to U.S.

?

? 
22

V. Preliminary econometric analysis of the discrepancies in eastbound trade

5.1 The basic model 

We apply a simple linear model of the discrepancy between the values of eastbound trade as 

reported by U.S. import data vs. those reported by China and Hong Kong. The model is 

estimated on a panel of 960 observations on data at the HS2 (chapter) level from 1996 to 

2005.21 It can be stated as follows, with time and chapter subscripts omitted for convenience: 

Discrepancy = $0 + $1 *processing trade share + $2 *state-owned enterprise share + $3 

*Hong Kong re-export share + $4*Hong Kong domestic export share + $5*U.S. import share 

passing through third countries + $6*U.S. re-exports as a share of U.S. exports + $7*time + 

$8*valuation indicator + $9*homogeneity + $10U.S. import tariffs + ,it

In some specifications, the model is estimated using fixed effects for HS2 chapters. In others, 

it is estimated using weighted data, with the weights being the mean of (China + Hong Kong) 

f.o.b. exports and U.S. f.o.b. imports.22 In other cases, the model is estimated with some 

outliers omitted. 

For each variable, a positive sign on the corresponding coefficient means that an increase in 

the variable is associated with the importer (United States) reporting relatively larger trade 

values, while a negative sign is associated with the exporters (China and Hong Kong) 

reporting relatively larger trade values. Because the analysis deals with one bilateral 

relationship, it is not designed to reveal whether the estimated effects have to do with 

importers in general and exporters in general, or with the United States as a particular 

importer and China and Hong Kong as particular exporters. A multilateral analysis would be 

required to reveal this.23

5.2 Data for dependent and explanatory variables 

The measure of the discrepancy used as the dependent variable is simply ER as defined in 

equation (2) in section 2.2. The underlying data come from original national sources 

(Customs General Administration of China, Census and Statistical Department of Hong 

Kong, and the version of U.S. Customs data maintained at the U.S. International Trade 

Commission). The data, available at a fine level of disaggregation (HS 6, 8, or 10) have been 

aggregated to HS2, using the “customs value” definition of U.S. imports to place data from 

all sources on a comparable F.O.B. basis. HS chapters 98 and 99 were deleted from the 

sample, since their definition and coverage are not standard across countries. 

 

21 Not all variables are currently available for 1995. There are only 96 chapters in HS 1-97 because one chapter 

(HS 77) is reserved for future use. 

22 We also experimented with weighting schemes using U.S. imports, or China + Hong Kong exports, as 

weights. All of the weighting schemes yield comparable results. 

23 In preliminary work, we experimented with using the absolute value of the discrepancy as a dependent 

variable, based on the idea that causes of bad trade data might induce random errors in either direction. We 

found that using these data, we obtained much better results using the actual discrepancy. This means that the 

difference between the importer and the exporter does matter, whatever that means in the context of these 

particular trading partners. 
23

In characterizing the data below, means and standard deviations calculated by HS chapter is 

used. For most of the variables in the data set, the variation by chapter exceeds the variation 

by year. In cases where we have so far only generated the variable for a single year (2000), 

that year’s values are presented. 

The share of processing trade, and the share of trade by state-owned enterprises are 

calculated from China Customs trade statistics. China Customs categorizes the trade data by 

type of firm trading, type of customs regime, and type of incentive scheme (such as special 

enterprise zones (SEZs), economic and technology development zones (ETDZs), etc. 

“Processing trade” represents the sum of the two customs regimes “process and assembly” 

and “processing with imported materials.” Defined this way, for a typical observation in our 

data set (an HS2 chapter in a given year) over 98 percent of exports is either “processing 

trade” or “normal trade,” the two most common customs regimes. Similarly, about 91 

percent of exports are either state-owned enterprises or foreign-invested enterprises (which 

includes both joint venture and wholly foreign invested firms), the two most common types 

of exporting firms. Thus, processing trade is high whenever normal trade is low, and vice 

versa, and similarly for exports of state-owned enterprises and foreign-invested enterprises. 

Not surprisingly, when we did the same analysis using normal trade instead of processing 

trade, or foreign-invested enterprises instead of state-owned enterprises, in most cases we 

found similar results with the opposite sign. 

 

Some chapters with a particularly high share of processing trade in Chinese exports to the 

United States over 1996-2006 are HS 86 (shipping containers and railway equipment), HS 18 

(cocoa), HS 37 (photographic and cinematographic goods), HS 85 (electronics), and HS 49 

(printing), for all of which the share of processing trade exceeds 90 percent on the average. 

On the low end, with an average share of processing trade below 1 percent, are HS 01 (live 

animals), HS 10 (cereals), HS 31 (fertilizers), HS 04 (dairy products), and HS 80 (tin and 

articles thereof). 

The share of China’s exports to the United States accounted for by SOEs is particularly high 

in HS 47 (pulp and paper), HS 24 (tobacco), HS 80 (tin and articles thereof), HS 1 (live 

animals), and HS 75 (nickel and articles thereof), ranging from 80-98 percent, and 

particularly low in HS 86 (shipping containers and railway equipment), HS 84 (machinery 

and computers), HS 17 (sugar and candy), HS 49 (printing), and HS 64 (footwear), ranging 

from 7 to 24 percent. 

Hong Kong re-exports of Chinese goods to the United States, and of Hong Kong domestic 

exports to the United States, is expressed as a share of China’s and Hong Kong’s total 

exports to the United States and are derived using Hong Kong’s and China’s data together. 

The share of U.S. imports from China and Hong Kong passing through third countries other 

than China and Hong Kong is based on unpublished data of the U.S. Census Bureau.24 

 

24 While we can identify the third countries in these data, we do not know whether the third countries consider 

the shipments to be re-exports or goods in transit. 
24

The share of China’s exports to the United States accounted for by Hong Kong’s re-exports 

is particularly high for HS 97 (art and antiques), HS 49 (printing), HS 91 (clocks and 

watches), HS 43 (fur and skins) and HS 71 (jewelry and precious stones), ranging from 58 to 

77 percent. The Hong Kong re-export share is particularly low for HS 86 (shipping 

containers and railway equipment), HS 31 (fertilizers), HS 27 (oil), HS 47 (wood pulp), and 

HS 02 (beef), ranging from 0.1 to 10 percent. The highest shares of Hong Kong domestic 

exports in total China-Hong Kong exports to the United States are for fabrics and apparel 

(HS 60, 61, 62), cotton (HS 52), and miscellaneous edible preparations (HS 21), ranging 

from 31-48 percent. There are seven HS chapters for which there are no domestic exports 

from Hong Kong to the United States in the period in question. 

The share of China-Hong Kong exports to the United States passing through third countries 

is particularly high for HS 50 (silk), HS 97 (art and antiques), HS 37 (photographic or 

cinematographic goods), HS 15 (fats and oils), and HS 51 (wool), ranging from 17 to 46 

percent. Particularly low shares of travel through third countries, all less than 1.5 percent, 

occur for HS 47 (wood pulp), HS 2 (beef), HS 1 (live animals), HS 64 (footwear), and HS 61 

(knit apparel). 

The measure of U.S. re-exports is the ratio, by HS2 and year, of U.S. re-exports to U.S. 

general imports, for all trading partners taken together. Because U.S. data identify the 

destination of re-exports but not the source of corresponding imports, it is not possible to 

measure directly the specific propensity of U.S. imports from China and Hong Kong to be reexported. The variable does, however, show a great deal of variation across chapters and is 

increasing over time, so it probably does capture some of the general tendency of goods to be 

re-exported. The time variable captures the general trend of the discrepancy to increase over 

time, in the direction of relatively larger U.S. data, for many of the HS chapters. 

The annual average share of all U.S. general imports, from all countries, which are reexported, is highest in HS 97 (art and antiques), HS 71 (gems and jewelry), HS 85 

(electronics), HS 08 (fruit and nuts), and HS 12 (oilseeds and miscellaneous vegetable 

products), ranging from 10-35 percent. Relatively low degrees of U.S. re-export, in all cases 

less than 1 percent, are observed for HS 27 (oil), HS 1 (live animals), HS 61 and 62 (apparel), 

and HS 79 (zinc and articles thereof). 

The indicator of valuation problems is simply the value share, in each HS chapter, of U.S. 

imports for which no unit of measurement is defined. For goods which are measured with 

units (e.g. kilograms, square kilometers, barrels, number of autos, etc) trade statistics report 

both a value and a quantity. Dividing the value by the quantity gives a value per unit, or unit 

value, which can be interpreted like a price. Having past data on unit values can give the 

customs authorities and indication of suspicious undervaluation or overvaluation. When unit 

values are absent, the possibility of manipulating the valuation is likely to be greater. For 

example, for most of the transactions in HS 97, art and antiques, there are no unit values, and 

thus no convenient bases for comparison. 

The value share of goods for which there were no unit values in 2000 was 99.9 percent in HS 

97 (art and antiques), and ranged from 48-89 percent for HS 67 (feathers, artificial flowers, 
25

and human hair), HS 90 (precision instruments), HS 94 (furniture and furnishings) and HS 95 

(toys, games, and sports equipment). There were 49 chapters of the HS for which all U.S. 

import data contained unit values in 2000. 

The measure of homogeneity describes whether each HS chapter contains mostly similar 

goods or a variety of goods. It may be that complicated goods are more subject to 

classification and valuation errors. It is defined in a matter similar to the HerfindahlHirschmann index in industrial organization, i.e. 

 

where sit represents the value share of each HS-10 commodity in U.S. general imports from 

the world within each HS2 chapter. The homogeneity index takes on values close to 1 for 

chapters with homogeneous products and values close to 0 for chapters with differentiated 

products. The index is relatively high for primary goods such as basic metals and grains, and 

relatively low for categories like electronics, machinery, and chemicals. 

In 2000, the homogeneity index was highest for HS 80 (tin and products), HS 75 (nickel and 

products), HS 97 (art and antiques; but this is misleading since it simply reflects the lack of 

categories), HS 47 (wood pulp) and HS 75 (zinc and products), ranging from 37-53 percent. 

Low homogeneity scores on the order of 1-2 percent were observed for HS 85 (machinery 

and computers), HS 73 (articles of iron and steel), HS 90 (instruments), HS 72 (iron and 

steel), and HS 62 (non-knit apparel). 

Both the valuation indicator and the homogeneity index are in principle measurable in both 

the time dimension and by HS2. At this point in the research, we have so far measured them 

only for a single year, the year 2000, approximately in the middle of our sample period. 

Thus we capture the variation across chapters but not across time. This has the consequence 

both that the variables drop out of our fixed-effects specifications (though we will address 

this in a revision) and that our current results for these variables may not generalize to the 

situation in which we measure them in a full panel (i x t). We suspect that the time variation 

in these variables is small relative to the cross-sectional variation, but this remains to be 

confirmed. 

The tariff variable for the United States is generated as the ratio of calculated duties collected 

to U.S. imports at customs value. This is in effect the same as trade-weighting the tariff. The 

variable as generated is likely to understate the tariff-equivalent effects of U.S. tariff-rate 

quotas in some agricultural commodities; at present we have made no adjustment for this. 

The annual average peak tariffs in the U.S. data, ranging from 12-16 percent ad valorem, are 

for HS 60-62 (fabrics and apparel), HS 24 (tobacco) and HS 55 (man-made staple fibers). 22 

chapters have annual average HS duties collected of less than 1 percent ad valorem, and 11 

have duties of less than 0.2 percent ad valorem. 

Unfortunately, there are no reliable measures of trade passing “in transit” (transshipped, not 

re-exported) from China to the United States through Hong Kong. We looked at several 

2 100 *

it s i Homogeneityi = ∑
26

tantalizing, but inadequate measures. Hong Kong Customs provide aggregate figures on the 

share of total tonnage which is shipped in transit per year. For such shipments, values and 

commodity categories are not observable. China Customs data identify shipments for which 

the consignment is Hong Kong but the ultimate destination is the United States. However, it 

is not possible to tell whether merchandise consigned for Hong Kong clears customs in 

Hong Kong (i.e. is a re-export) or simply passes through physically (i.e. is transshipped/in 

transit). Thus, it is not possible to test directly the hypothesis that discrepancies related to 

goods in transit may be different from either re-exports on the one hand or “pure” direct 

shipments on the other hand. Conceptually, these goods are included in our measure of 

direct shipments from China to the United States, but this should be interpreted with caution. 

We plan to use the unpublished U.S. shipping data obtained from U.S. census recently to 

further explore this issue in our next revision. 

Descriptive statistics for the variables used in the analysis are presented in Table 11. 

5.3 Analytical Challenges 

There are some significant issues that arise in the analysis of the data. The reader will note 

that many of the variables are expressed as ratios to total imports or exports, using either 

China + Hong Kong data, or U.S. data, as the denominator. Of course, we do not know what 

the true values of the trade flows are, only what either side reports; this is the whole point of 

the analysis. Using either side’s data as the denominator of a ratio is likely to introduce 

measurement error into the measured dependent variables, and possibly bias. There are a 

number of potential ways of handling this problem, ranging from simple ones (use the other 

side’s value as the denominator, where this can be done: generally this only makes sense if 

the numerator data refers to Hong Kong) to complex ones, such as iterating back and forth 

between estimates of the “true” values and new estimates of the independent variables. The 

present method simply measures each ratio at the point in the data where it is most naturally 

defined. 

The second issue is that there is clearly a great deal of difference between the discrepancies 

and their behavior in one sector and another. This is plainly visible in the raw data, and is 

also apparent in that the goodness-of-fit measures of the fixed-effects estimates are so much 

higher than the comparable OLS estimates. Moreover, some of the worst valuation problems 

are in sectors that account for very little trade according to either side’s data. This raises the 

question of whether the purpose of the analysis is to find the main determinants of the $46 

billion discrepancy, in which case it makes sense to use data weighted by the size of the trade 

flows, or whether the purpose is to identify the characteristics of the chapters with the worst 

discrepancies, in which case it makes sense to use un-weighted data. We use both 

approaches. 

In order to provide an additional test for robustness, we perform an additional set of estimates 

systematically excluding outliers using a method similar to that in Leamer (1985, chapter 5). 

We identified all the chapters for which the values of the independent variable or any of the 

dependent variable were outliers, in the top or bottom 3. This amounted to 28 of the 96 

chapters. We then excluded each of the chapters from the sample, and identified as outliers 
27

cases in which the exclusion of the chapter led to a substantial change in any of the 

regression coefficients. This method identified four sectors as outliers: 

HS 24, tobacco and tobacco products (high tariffs); HS 67, products made of feathers or 

human hair, and artificial flowers (few unit values); HS 86, railway and related goods (these 

are mostly shipping containers in HS 860900 which are usually not recorded as U.S. imports 

because they are “instruments of trade”, thus they have a large discrepancy in the opposite 

direction (exporters’ data is larger) and whose exports from China are heavily recorded as 

processing trade of foreign-invested enterprises), and HS 97, art and antiques (virtually no 

unit values, and a very high rate of transshipment through Hong Kong) 

We added one additional chapter, HS 93 (armaments and ammunition), which has a very 

large discrepancy (importers’ values larger) even though it did not have a very large effect on 

the regression results when excluded. Anecdotal evidence indicates that Chinese export data 

may frequently record in HS 98 transactions which U.S. import data record in HS 93. 

Estimates presented below as being “without outliers” exclude chapters 24, 67, 86, 93, and 

97 as a group. The trade in these chapters accounts for less than 1 percent of recorded 

China/Hong Kong exports to the United States, and less than 2 percent of recorded U.S. 

imports from China and Hong Kong. 

5.4 Primary results 

Table 12 presents the results of regressions using the full set of available variables, 

while Table 13 presents the results of fixed-effects specifications which (at present) exclude 

the valuation and homogeneity variables, and comparable specifications using the same set of 

regressors for comparison purposes. The results confirm the impression that both the size of 

the discrepancy and the variables which correlate with the discrepancy vary greatly from 

sector to sector. For one thing, the inclusion of sector-specific intercepts in the fixed-effects 

specifications soak up a good deal of variation in the data, increasing R2

 from .25 to .77 in 

the full sample and .22 to .73 in the sample omitting outliers. In OLS, omitting outliers while 

simultaneously weighting the data improves the goodness-of-fit to about .40. The two 

procedures we used to vary the relative importance of the different chapters, weighting and 

the omission of outliers, often have the effect of changing the estimated signs of the 

coefficients, often from significantly positive to significantly negative. All this suggests that 

the general determinants of the currently $46 billion discrepancy are, in some respects, 

different from the causes of the discrepancy for some of the smaller sectors with particularly 

bad data. 

 The robust determinants of the discrepancy, those which show up with the same sign 

and significant in most or all specifications, are as follows: 

Valuation problems: For products with no recorded unit values, which might be easy to 

undervalue, U.S. import data are significantly larger than China’s export data. This is true 

even after we exclude the outliers, which include HS 97 (art and antiques) and HS 67 

(feathers, artificial flowers, human hair and wigs) which are especially difficult to value. 
28

This is an interesting result and suggests further exploration into the extent that mis-valuation 

may be attributed to deliberate strategies on the part of traders. 

U.S. import tariffs: A one-percent increase in the U.S. ad valorem tariff is associated with a 

decrease in the discrepancy score of around 0.7 to over 2.4. This suggests that the exporters’ 

numbers are relatively high when U.S. import tariffs are high. This pattern could be 

explained if exporters of high-tariff goods record relatively high values to the exporting 

authority (perhaps to report high revenues or profits in the enterprise) and relatively low 

values to the importing authority to avoid the tariff. It could also be that the higher scrutiny 

given by U.S. customs to revenue-producing shipments leads to an improvement in the 

data.25

U.S. re-exports as a share of U.S. imports: A higher share of U.S. re-exports is associated 

in all specifications with higher China-Hong Kong data relative to U.S. data. This does not 

have an obvious explanation. One possibility is that exporters record as exports to the 

United States goods which are ultimately re-routed to third countries, and that the same 

goods are treated in the United States as goods in transit and not recorded as statistical trade. 

There are other, more complex, possibilities 

Time: Even after controlling for all the other variables in the analysis, the tendency of U.S. 

import data to grow larger than China/Hong Kong export data shows a marked time trend, 

with the discrepancy index increasing by 1.2 to 2.9 points every year for reasons not related 

to the time trends of the other variables. 

The results for type of Chinese customs regime, type of enterprise, variables pertaining to 

Hong Kong, third-country U.S. import share, and homogeneity are so far not robust with 

respect to specification. 

VI. Conclusion and directions for future work 

Our results both for valuation problems and for U.S. import tariffs, which can be avoided by 

under-valuation, suggest that reporting of different values to importing and exporting 

authorities might be a significant source of discrepancies in trade data. The misreporting of 

origins and destinations due to goods passing through many countries is also likely to be 

important. The fact that we find some variables to be very important in some specifications 

but less important or having the opposite sign is not proof that those variables are not 

important. It is more likely to mean that identifying how they are important requires a deeper 

analysis than we have done so far. 

The most fruitful extension of this work is likely to be the extension of the analysis to the 

five-way mirror made possible by the detailed customs data of the three reporters. The 

sources of the discrepancies in direct trade, in third-country trade, and in the various Hong 

Kong -related trade flows are likely to be different, as are the incentives either to misreport 

 

25 We are indebted to Shang-Jin Wei for this idea. 
29

each one or misattribute one for the other. A fuller behavioral model of the reporting 

practices of traders would be useful to this work. 

The econometric analysis can also be done on the westbound trade (United States as exporter, 

China and Hong Kong as importers). Even though the overall discrepancies are much less 

severe in the westbound trade, the pattern of existing discrepancies may show some 

commonalities. The analysis already presented can be done at a higher degree of 

disaggregation, and the definitions of some of the variables improved. We also need to look 

further into the possibility that re-exports, which fully enter and leave the customs territory of 

Hong Kong and are often subject to a markup in price, may be confused with transshipments, 

which are simply moved from vessel to vessel without clearing customs. 

We have taken preliminary steps to analyze the data for China and multiple trading partners. 

Using multilateral data can help to show which sources of the discrepancy are associated 

with particular roles in trade (importer, exporter, or re-exporter) and which are associated 

with particular countries or customs territories in different geographical situations or at 

different stages of economic development. 

Persons involved in customs agencies and private import-export operations are likely to have 

insights into the matters analyzed in this paper that may confirm, contradict, or otherwise 

place in a new light the results we have gotten by purely statistical means. It would be very 

useful to compare the insights of people with operational contact with trading operations with 

those which appear to be emerging from the present analysis. 
30

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32

Table 1. Trade and Cargo Shipping Statistics Reported By China and Hong Kong, 1995 to 2004 

Section A China’s exports 

 1995 1996 1997 1998 1999 2000 2001 2002 2003 2004 

Hong Kong as final 

destination 35,988 32,904 43,798 38,785 36,917 44,530 46,489 58,465 76,289 100,878 

Hong Kong as 

consigned destination 74,493 64,209 77,852 76,547 72,674 82,409 83,423 99,295 123,600 154,885 

China 

Reported 

Exports 

(fob) Export via Hong Kong 

(Transshipment) 38,505 31,305 34,054 37,762 35,757 37,879 36,934 40,829 47,312 54,007 

Hong Kong total 

Imports from China (cif) 69,736 73,758 78,581 74,966 78,312 91,771 87,445 91,944 100,889 117,909 Hong Kong 

Reported 

Imports Hong Kong-China 

FOB/CIF ratio 0.9903 0.9903 0.9912 0.9919 0.991 0.9916 0.9915 0.992 0.9921 0.9927 

Hong Kong total 

Imports from China 

(fob) 69,060 73,042 77,889 74,359 77,607 91,000 86,701 91,209 100,092 117,048 

Statistical discrepancy 

(Million U.S. Dollars) 5,433 -8,834 -37 2,188 -4,933 -8,591 -3,278 8,086 23,508 37,837 

Adjustment 

Statistical discrepancy 

(Percent) 7.3 -13.8 0.0 2.9 -6.8 -10.4 -3.9 8.1 19.0 24.4 

Hong Kong Imports1 

from China 17,028 16,590 17,112 17,806 16,893 19,334 22,422 24,983 24,723 22,313 

Inward transshipment2

for China 7,959 6,797 7,183 7,234 9,267 10,805 10,958 13,519 17,431 21,417 

Total Cargo Discharged 24,986 23,387 24,294 25,039 26,160 30,139 33,381 38,502 42,154 43,729 

Cargo 

Shipping, 

1000 Metric 

Ton 

Inward Transshipment 

as % of total 31.9 29.1 29.6 28.9 35.4 35.9 32.8 35.1 41.4 49.0 

Section B China's imports 

Re-export to China for 

third countries 49,644 54,015 57,334 52,597 51,455 62,742 63,672 73,326 90,637 109,225 

Domestic Export to 

China 8,216 7,967 8,249 7,239 6,498 6,951 6,353 5,305 4,720 4,866 

Hong Kong 

Reported 

Exports 

(fob) Total Exports to China 57,859 61,982 65,583 59,836 57,953 69,693 70,025 78,631 95,357 114,091 

Imports originated from 

Hong 8,599 7,839 6,990 6,667 6,893 9,431 9,420 10,741 11,119 11,800 

Total imports via Hong 

Kong 60,165 55,046 53,808 52,762 62,391 76,384 82,496 104,979 132,064 166,529 

China 

Reported 

Imports(cif) Imports originated from 

third countries 51,566 47,207 46,818 46,096 55,497 66,952 73,076 94,237 120,945 154,729 

Hong Kong-China 

FOB/CIF ratio 0.9903 0.9903 0.9912 0.9919 0.991 0.9916 0.9915 0.992 0.9921 0.9927 

Total imports via Hong 

Kong (fob) 59,582 54,512 53,334 52,335 61,829 75,742 81,795 104,139 131,021 165,314 

Statistical discrepancy 

(Million U.S. Dollars) 1,723 -7,471 -12,249 -7,501 3,876 6,049 11,771 25,508 35,664 51,222 

Adjustment 

Statistical discrepancy 

(Percent) 2.9 -13.7 -23.0 -14.3 6.3 8.0 14.4 24.5 27.2 31.0 

Hong Kong Exports1 to 

China 14,711 18,433 21,533 20,769 14,920 14,830 13,013 12,318 13,368 13,653 

OutwardTransshipment2

to China 6,876 7,457 8,540 9,417 12,494 15,655 18,776 21,673 23,838 24,680 

Total cargo loaded 21,588 25,890 30,072 30,186 27,413 30,485 31,789 33,991 37,205 38,333 

Cargo 

Shipping, 

1000 Metric 

Ton 

Outward Transshipment 

as percent of total 31.9 28.8 28.4 31.2 45.6 51.4 59.1 63.8 64.1 64.4 

Data source: All China reported trade data are from China Customs Authority; all Hong Kong reported trade data are from Hong Kong 

Census and Statistics Department. Port Cargo data are from Hong Kong Census and Statistics Department. The cargo statistics from 

1995 to 1999 refer to HK’s seaborne cargo statistics, while those for 2000-2004 refer to Hong Kong's seaborne and river port cargo 

statistics. The river cargo statistics have been compiled in recent years given the growing importance of the river trade between Hong 

Kong and the mainland of China, particularly the Pearl River Delta (PRD) region. Port cargo movements between HK and places other 

than the mainland of China and Macao are all classified as seaborne cargo movement. 
33

Table 2. Trade and Cargo Shipping Statistics Reported By China and Hong Kong, 1995 to 2004 

 1995 1996 1997 1998 1999 2000 2001 2002 2003 2004 

Section A China's and Hong Kong’s exports to the United States 

Trade Statistics 

Hong Kong Domestic exports 7,918 6,964 7,114 7,081 6,620 6,987 6,102 5,374 5,025 4,961 

Hong Kong re-export 29,860 31,335 33,760 33,551 34,731 39,924 36,183 37,318 36,610 38,901 

China reported exports via Hong 

Kong 14,265 12,458 14,110 15,774 14,699 14,638 13,899 15,354 16,308 19,020 

Total exports via Hong Kong 52,043 50,757 54,984 56,406 56,051 61,549 56,183 58,045 57,943 62,882 

China reported as % of total 27.4 24.5 25.7 28.0 26.2 23.8 24.7 26.5 28.1 30.2 

 

Cargo Shipping Statistics 

Hong Kong Exports1to US 5,566 5,286 5,483 5,893 7,038 7,781 7,287 7,374 6,663 7,053 

Outward transshipment2 to US 2,024 2,282 2,519 2,495 2,800 2,979 3,210 3,668 3,725 4,474 

Total Cargo loaded for US 7,590 7,568 8,002 8,388 9,838 10,759 10,497 11,043 10,388 11,526 

Outward Transshipment as percent 

of total 26.7 30.2 31.5 29.7 28.5 27.7 30.6 33.2 35.9 38.8 

Section B China's and Hong Kong’s imports from the United States

Trade Statistics 

Hong Kong Import from US 14,876 15,653 16,195 13,756 12,706 14,478 13,456 11,729 12,679 14,380 

Hong Kong re-export to China for 

US 4,982 5,866 5,965 5,294 5,373 6,109 6,466 6,197 6,238 5,787 

China reported import via Hong 

Kong 4,877 4,565 4,351 4,778 6,397 6,189 6,978 7,018 7,593 7,613 

Total imports via Hong Kong 19,753 20,218 20,546 18,534 19,103 20,667 20,434 18,748 20,271 21,994 

China reported as % of total 24.7 22.6 21.2 25.8 33.5 29.9 34.1 37.4 37.5 34.6 

 

Cargo Shipping Statistics 

Hong Kong Imports1 from US 5,164 5,081 5,486 4,641 3,998 3,785 3,321 3,690 3,441 3,681 

Inward Transshipment2 from US 2,613 2,320 2,312 1,973 2,239 2,553 3,015 2,827 3,120 3,997 

Total cargo discharged 7,777 7,401 7,798 6,613 6,237 6,339 6,336 6,517 6,561 7,678 

Inward Transshipment as percent of 

total 33.6 31.3 29.6 29.8 35.9 40.3 47.6 43.4 47.6 52.1 

Data source: All China reported trade data are from China Customs Authority; all Hong Kong reported trade 

data are from Hong Kong Census and Statistics Department. All data reported by the United State are from 

Census Bureau, U.S. Department of Commerce. Port Cargo data are from Hong Kong Census and Statistics 

Department. 

Note for tables 1 and 2: 

1. It refers to goods imported into Hong Kong or exported/re-exported from Hong Kong. Goods transshipped in 

Hong Kong under a through bill of lading are not included. Goods in transit are also not included. 

2. It refers to goods transshipped in Hong Kong under a through bill of lading from a place outside Hong Kong 

to another place outside Hong Kong but is or is to be removed from one vessel (ship, vehicle, train or aircraft) 

and either returned to the same vessel or transferred to another vessel within Hong Kong waters. 
34

Table 3. Trade Statistics Reported by China, Hong Kong and the United States and Statistical Discrepancies, 1995-2006(Eastbo

dollars)

Year 1995 1996 1997 1998 1999 2000 2001 2002 200US reported imports from China (fob) + 45,555 51,495 62,552 71,156 81,786 100,063 102,280 125,168 152,37US reported imports from Hong Kong (fob) + 10,294 9,867 10,297 10,538 10,531 11,452 9,650 9,328 8,85Geographical coverage adjustment for US reported data From China - 106 132 145 152 195 216 256 299 36From Hong Kong - 36 67 50 60 43 35 26 18 2US reported imports from China & Hong Kong (fob) 55,707 61,164 72,654 81,483 92,079 111,264 111,648 134,180 160,83Statistical Discrepancy (Million US dollars) - -4,528 -1,734 1,535 5,538 11,449 15,711 18,023 24,543 29,93

China & Hong Kong reported exports to US (fob) 60,235 62,898 71,119 75,945 80,630 95,553 93,625 109,637 130,90

China reported exports to US (fob) + 24,713 26,709 32,716 37,965 42,016 52,142 54,273 69,951 92,47Hong Kong reported domestic exports to US(fob) + 7,918 6,964 7,114 7,081 6,620 6,987 6,102 5,374 5,02

Hong Kong reported re-exports to US for China(fob) + 27,604 29,225 31,289 30,899 31,994 36,424 33,251 34,313 33,40Statistical Discrepancy as % of US reported imports -8.13 -2.83 2.11 6.80 12.43 14.12 16.14 18.29 18.6Statistical Discrepancy as % of sum of US, China & Hong Kong reported data, ITC consistency indicators (total) -7.81 -2.80 2.14 7.04 13.26 15.19 17.56 20.13 20.5Hong Kong re-export as % of U.S. total imports from China 60.6 56.8 50.0 43.4 39.1 36.4 32.5 27.4 21Goods originated from China as % of total Hong Kong re-export to US 92.4 93.3 92.7 92.1 92.1 91.2 91.9 91.9 91

Data source: All China reported data are from China Customs Authority; all Hong Kong reported data are from Hong Kong Census an

all United State reported data are from International Trade Commission Oracle database. The data include HS Chapter 1 to 99. Note: Geographical adjustments are based on U.S. reported data. China & Hong Kong reported data do not include Virgin Island and P
35

Table 4. Discrepancy Indexes of Trade Statistics Reported by China, Hong Kong and United States in Major HS 

sections, 1995-2006 (export to the United States, in percent) 

Year 1995 1996 1997 1998 1999 2000 2001 2002 2003 2004 2005 2006 

Statistical Discrepancy as % of U.S. reported imports a 

Live animals and animal products -3.4 6.1 20.3 17.3 15.2 21.2 29.4 23.7 25.4 23.9 18.5 33.9 

Vegetable products 5.1 14.4 21.0 25.6 30.9 34.3 26.6 27.8 21.3 24.5 23.8 14.5 

Animal and vegetable fats and oils 9.8 44.4 8.9 17.2 -4.9 20.5 11.7 -1.1 6.7 2.5 -4.5 11.3 

Prepared foodstuffs, beverages and tobacco -4.7 1.4 -3.4 -6.6 1.5 -22.8 -16.7 -16.1 -10.2 3.5 0.9 -16.0 

Mineral products 0.5 4.4 15.1 5.7 11.0 7.5 8.6 9.2 -5.4 12.5 -2.4 -9.1 

Products of the chemical or allied industries -10.1 0.5 -1.3 0.1 7.3 0.5 -1.1 -5.6 -6.0 -4.6 0.7 2.1 

Plastics and rubber -24.3 -24.0 -20.5 -24.9 -19.2 -16.7 -6.2 0.5 7.9 10.3 13.3 11.0 

Raw hides and skins, leather, fur skins -18.7 -14.8 -5.7 -2.3 -1.7 0.2 0.7 4.2 7.7 8.4 11.9 13.9 

Wood and cork articles -29.9 -13.6 -3.7 11.1 14.2 15.2 16.2 14.3 15.8 12.0 13.9 11.7 

Wood pulp, paper and paperboard articles 10.3 17.0 10.2 14.4 18.0 23.4 23.0 24.0 26.6 26.0 28.2 25.9 

Textiles -0.3 1.2 5.2 3.8 4.7 3.5 4.9 7.0 8.1 10.5 0.1 -2.0 

Footwear, headgear and umbrellas -29.8 -23.4 -16.4 -0.4 7.6 7.9 14.4 18.3 20.6 21.4 23.2 24.5 

Articles of stone, plaster, cement, ceramic & glass -6.1 7.9 15.9 20.0 29.6 37.3 39.7 41.0 39.3 35.1 32.5 29.2 

Pearls, precious stones and metals 10.5 14.5 13.4 11.2 8.7 12.4 9.4 5.2 -0.4 1.1 3.9 4.3 

Base metals -10.5 -6.9 -3.8 -6.9 4.3 5.9 11.4 8.9 11.3 8.8 10.6 7.3 

Machinery and mechanical appliances 10.7 6.1 7.0 11.2 25.9 29.9 27.8 27.4 20.1 25.8 24.5 19.8 

Electrical machinery and equipment -7.3 -0.1 5.3 10.9 11.8 10.3 9.8 12.4 11.8 12.8 13.6 12.2 

Vehicles, aircraft, vessels and other transport 

equipment -88.3 -53.4 -23.9 -41.1 -28.4 7.5 -11.3 -10.5 -34.7 -46.7 -43.0 -35.8 

Medical instruments, musical instruments, clocks 

and watches -13.8 -11.3 -7.5 -2.7 -2.9 -1.8 -5.3 -3.8 8.6 6.9 -10.4 -22.5 

Arms and ammunition 31.2 52.8 49.6 28.0 43.3 68.3 68.8 82.3 86.2 84.1 81.0 78.9 

Miscellaneous manufactured articles -9.7 0.1 5.3 12.8 19.2 22.1 29.0 31.8 36.9 36.7 38.0 38.1 

Works of art, collectors' pieces and antiques 41.2 51.7 50.9 65.8 71.2 77.7 79.5 64.0 77.6 63.6 53.1 65.8 

Totalc -9.7 -4.2 0.7 5.4 11.0 12.7 14.8 17.1 17.4 18.4 17.0 14.9 

Statistical Discrepancy as % of sum of US, China & Hong Kong reported data, consistency indicators (total)b 

Live animals and animal products -3.4 6.3 22.6 18.9 16.4 23.8 34.4 26.9 29.1 27.2 20.4 40.8 

Vegetable products 5.3 15.5 23.5 29.3 36.5 41.4 30.7 32.3 23.8 28.0 27.0 15.7 

Animal and vegetable fats and oils 10.3 57.1 9.3 18.8 -4.8 22.8 12.4 -1.1 6.9 2.5 -4.4 12.0 

Prepared foodstuffs, beverages and tobacco -4.6 1.4 -3.4 -6.4 1.6 -20.5 -15.4 -14.9 -9.7 3.5 1.0 -14.8 

Mineral products 0.5 4.5 16.3 5.9 11.7 7.8 9.0 9.7 -5.2 13.3 -2.4 -8.7 

Products of the chemical or allied industries -9.6 0.4 -1.3 0.1 7.6 0.4 -1.3 -5.8 -6.0 -4.6 0.6 2.2 

Plastics and rubber -21.7 -21.4 -18.6 -22.2 -17.6 -15.4 -6.0 0.5 8.2 10.9 14.3 11.6 

Raw hides and skins, leather, fur skins -17.1 -13.8 -5.6 -2.2 -1.7 0.2 0.7 4.3 8.0 8.8 12.7 14.9 

Wood and cork articles -26.0 -12.8 -3.6 11.8 15.3 16.5 17.7 15.4 17.2 12.7 15.0 12.5 

Wood pulp, paper and paperboard articles 10.9 18.6 10.7 15.5 19.8 26.6 25.9 27.2 30.6 29.9 32.9 29.7 

Textiles -0.3 1.2 5.4 3.9 4.8 3.6 5.0 7.2 8.4 11.0 0.1 -2.0 

Footwear, headgear and umbrellas -25.9 -21.0 -15.2 -0.4 7.9 8.2 15.6 20.2 22.9 23.9 26.3 27.9 

Articles of stone, plaster, cement, ceramic & glass -5.9 8.2 17.2 22.2 34.7 45.8 49.5 51.5 48.8 42.6 38.8 34.2 

Pearls, precious stones and metals 11.1 15.6 14.3 11.8 9.1 13.2 9.9 5.4 -0.4 1.1 3.9 4.3 

Base metals -10.0 -6.7 -3.7 -6.7 4.4 6.0 12.1 9.3 12.0 9.2 11.2 7.6 

Machinery and mechanical appliances 11.3 6.3 7.2 11.8 29.7 35.2 32.3 31.8 22.3 29.6 28.0 21.9 

Electrical machinery and equipment -7.0 -0.1 5.5 11.5 12.6 10.9 10.3 13.2 12.6 13.7 14.6 13.0 

Vehicles, aircraft, vessels and other transport equi. -61.3 -42.1 -21.3 -34.1 -24.9 7.8 -10.7 -10.0 -29.6 -37.9 -35.4 -30.4 

Medical instruments, musical instruments, clocks 

and watches -12.9 -10.7 -7.3 -2.7 -2.9 -1.8 -5.2 -3.8 9.0 7.1 -9.9 -20.2 

Arms and ammunition 37.0 71.8 65.9 32.6 55.3 103.8 104.9 139.7 151.3 145.1 136.2 130.3 

Miscellaneous manufactured articles -9.2 0.1 5.5 13.6 21.3 24.8 33.9 37.8 45.3 44.9 46.9 47.1 

Works of art, collectors' pieces and antiques 51.9 69.8 68.2 98.0 110.6 127.0 132.0 94.2 126.9 93.2 72.4 98.0 

Totalc -4.6 -2.1 0.4 2.8 5.8 6.8 8.0 9.3 9.5 10.1 9.3 16.0 

Data source: All China reported data are from China Customs Authority; all Hong Kong reported data are from Hong Kong Census and 

Statistics Department; all United State reported data are from International Trade Commission Oracle database, both exports and imports 

are measured on fob price. a. Defined in equation (1) of the paper. b. Defined in equation (2) of the paper, which is modified from similar 

index developed by International Trade Center at UNCTAD/WTO in Geneva c. It includes HS Chapter 1-97. 
36

Table 5 Discrepancy Indexes of Trade Statistics Reported by China, Hong Kong and their Major Partners, 

1995-2004 (export to partner countries, in percent) 

Year 1995 1996 1997 1998 1999 2000 2001 2002 2003 2004 

Statistical Discrepancy as % of U.S. reported importsa

Argentina 8.5 5.0 14.5 20.0 20.9 15.3 25.5 37.8 28.4 29.1 

Australia 0.7 4.6 0.7 1.5 7.1 11.3 9.3 13.4 14.4 18.0 

Brazil -44.1 -14.1 -17.5 -19.4 -9.4 -6.8 -5.3 -1.7 -3.3 -1.1 

Canada 8.8 11.5 18.3 21.3 26.2 28.8 32.0 33.6 39.2 41.4 

Chile -102.6 -66.4 -63.7 -53.3 -51.7 -37.7 -20.6 -18.4 -20.6 -4.0 

EU15 4.1 8.5 9.2 10.6 15.4 14.4 14.6 19.0 18.6 21.5 

EU10 -17.4 5.8 10.4 21.4 23.2 16.7 23.5 32.1 36.0 34.5 

India 4.3 0.1 6.7 8.8 20.7 9.1 14.8 13.1 22.7 18.8 

Indonesia -27.1 -20.3 -39.5 -35.4 -64.3 -63.6 -68.8 -54.9 -66.5 -64.2 

Israel 11.7 17.8 16.9 23.3 25.5 28.5 25.0 35.0 15.5 20.9 

Japan 2.1 2.9 3.9 1.5 7.9 8.2 6.1 7.1 7.6 9.9 

Korea 3.4 7.3 5.2 -5.7 6.5 7.0 1.8 8.5 8.9 6.2 

Malaysia 23.5 24.4 19.0 19.2 23.9 25.8 19.6 21.5 16.7 23.0 

Mexico 14.7 37.9 40.1 29.5 31.3 24.8 35.0 36.7 57.9 59.2 

New Zealand 20.5 24.0 25.6 19.6 28.2 26.7 31.7 33.4 36.6 36.7 

Norway 28.1 15.3 -0.6 30.0 34.4 26.2 36.9 58.7 36.7 47.4 

Panama -6176.4 -4514.4 -7333.6 -4495.3 -4358.4 -4813.5 -4644.1 -3105.5 -2920.3 

Saudi Arabia -45.2 -38.8 -33.9 -34.4 -25.0 -13.5 -10.6 -4.8 

Singapore 12.2 13.5 16.6 9.3 14.5 12.3 14.8 16.1 13.7 15.6 

South Africa -43.9 -38.4 -32.2 -36.5 -24.2 -23.2 -12.4 -4.7 3.1 11.3 

Switzerland 15.7 11.7 6.3 10.9 9.2 15.4 18.9 30.4 29.7 17.5 

Thailand 2.4 13.0 11.8 17.5 20.8 17.1 16.8 22.0 18.3 

United States -3.2 1.3 5.6 10.3 16.9 18.7 20.3 22.2 22.9 23.8 

Venezuela -188.5 -154.9 -268.4 -163.8 -25.4 -27.6 -31.9 -43.8 -14.5 -38.2 

Philippines -2.7 -3.5 0.4 -6.3 -31.4 -26.2 -33.7 -31.9 -41.7 

Russian Federation -105.5 -97.0 -79.6 -78.7 -149.8 -77.6 -54.6 -90.0 -99.6 

Other reporting 

countries 

-22.5 -26.7 -18.9 -12.7 -12.3 -13.9 -3.7 -8.9 -15.7 -5.3 

All reporting partners -0.8 2.4 4.1 6.0 11.9 11.7 12.6 15.6 15.8 18.2 

Statistical Discrepancy as % of mean of Partner, China & Hong Kong reported data, consistency indicators (total)b

Argentina 8.9 5.1 15.6 22.2 23.4 16.6 29.2 46.6 33.1 34.0 

Australia 0.7 4.7 0.7 1.5 7.3 12.0 9.8 14.3 15.6 19.8 

Brazil -36.1 -13.2 -16.1 -17.7 -8.9 -6.6 -5.2 -1.7 -3.3 -1.1 

Canada 9.2 12.2 20.1 23.9 30.1 33.7 38.1 40.4 48.7 52.2 

Chile -67.8 -49.9 -48.3 -42.1 -41.1 -31.7 -18.7 -16.9 -18.7 -3.9 

EU15 4.2 8.9 9.6 11.2 16.7 15.6 15.8 20.9 20.5 24.1 

EU10 -16.0 5.9 11.0 24.0 26.3 18.3 26.6 38.3 43.9 41.7 

India 4.4 0.1 6.9 9.2 23.1 9.6 16.0 14.0 25.7 20.8 

Indonesia -23.9 -18.5 -33.0 -30.1 -48.7 -48.3 -51.2 -43.1 -49.9 -48.6 

Israel 12.4 19.6 18.5 26.4 29.2 33.2 28.6 42.5 16.9 23.3 

Japan 2.1 3.0 3.9 1.6 8.3 8.6 6.2 7.4 7.9 10.4 

Korea 3.4 7.6 5.4 -5.5 6.7 7.2 1.8 8.9 9.3 6.4 

Malaysia 26.7 27.7 21.1 21.2 27.2 29.6 21.7 24.1 18.2 26.0 

Mexico 15.9 46.8 50.1 34.6 37.1 28.3 42.4 44.9 81.5 84.1 

New Zealand 22.9 27.3 29.4 21.7 32.8 30.8 37.6 40.1 44.8 44.9 

Norway 32.7 16.6 -0.6 35.2 41.5 30.2 45.3 83.1 44.9 62.0 

Panama -193.7 -191.5 -194.7 -191.5 -191.2 -192.0 -191.7 -187.9 -187.2 

Saudi Arabia -36.9 -32.5 -29.0 -29.4 -22.2 -12.6 -10.1 -4.7 

Singapore 13.0 14.5 18.1 9.7 15.6 13.1 16.0 17.5 14.7 17.0 

South Africa -36.0 -32.2 -27.7 -30.9 -21.6 -20.8 -11.7 -4.6 3.1 11.9 

Switzerland 17.1 12.4 6.5 11.5 9.7 16.7 20.8 35.8 34.9 19.2 

Thailand 2.4 13.9 12.6 19.2 23.3 18.7 18.4 24.8 20.1 

United States -3.2 1.3 5.8 10.9 18.5 20.6 22.5 25.0 25.9 27.0 

Venezuela -97.0 -87.3 -114.6 -90.0 -22.5 -24.3 -27.5 -35.9 -13.5 -32.0 

Philippines -2.7 -3.4 0.4 -6.1 -27.1 -23.2 -28.8 -27.5 -34.5 

Russian Federation -69.1 -65.3 -57.0 -56.5 -85.7 -55.9 -42.9 -62.1 -66.5 

Other reporting 

countries 

-20.2 -23.6 -17.2 -11.9 -11.6 -13.0 -3.6 -8.5 -14.5 -5.1 

All reporting partners -0.8 2.4 4.1 6.1 12.7 12.4 13.4 16.9 17.1 20.0 
37

Table 5, continued 

Discrepancy Indexes of Trade Statistics Reported by China, Hong Kong and their Major Partners, 1995-2004 

(export to partner countries, in percent) cont. 

Year 1995 1996 1997 1998 1999 2000 2001 2002 2003 2004 

Consistency indicators (absolute average)c 

Argentina 20.5 25.3 32.1 36.6 34.9 29.9 38.4 56.6 42.7 39.5 

Australia 14.8 14.3 14.3 15.0 16.8 20.0 19.2 20.5 21.1 24.7 

Brazil 45.2 30.4 34.3 34.9 30.0 33.8 20.8 23.0 20.9 21.9 

Canada 15.4 20.3 27.6 30.8 33.5 37.0 41.1 42.6 49.1 52.5 

Chile 70.7 52.8 51.2 46.0 45.9 36.3 26.4 22.4 24.6 21.4 

EU15 14.2 13.7 14.5 16.4 20.4 20.2 20.2 24.5 24.1 28.4 

EU10 65.7 64.2 77.2 78.7 72.8 70.8 69.3 70.3 69.0 49.7 

India 41.8 44.6 31.7 43.5 48.7 39.1 34.2 35.5 36.9 35.3 

Indonesia 40.4 42.7 47.5 62.2 71.5 63.1 63.7 53.2 55.8 54.6 

Israel 32.1 30.4 27.5 33.5 40.6 43.0 40.9 53.0 30.2 36.5 

Japan 14.3 13.1 12.8 12.0 12.8 12.4 10.5 12.0 11.9 12.3 

Korea 20.5 23.8 16.8 21.6 19.6 19.9 17.1 21.6 22.7 18.1 

Malaysia 37.3 35.7 34.5 34.8 39.2 39.7 34.0 33.3 33.7 39.7 

Mexico 52.6 55.8 60.4 45.4 52.5 48.5 65.8 71.6 97.9 101.1 

New Zealand 27.1 29.4 33.0 36.3 36.0 32.8 39.6 45.9 47.2 47.1 

Norway 44.7 48.6 61.9 46.6 52.0 57.2 52.8 84.4 74.7 71.2 

Panama 194.1 191.8 194.8 192.1 191.4 192.1 191.9 188.0 187.3 

Saudi Arabia 43.5 43.7 33.0 38.4 32.6 35.8 35.3 41.2 

Singapore 19.4 23.8 24.0 19.3 23.6 20.3 23.6 28.6 28.7 29.0 

South Africa 50.4 46.5 40.3 42.5 40.8 35.0 28.4 31.8 31.1 32.7 

Switzerland 39.1 43.0 47.0 46.2 44.7 41.3 37.3 45.2 49.0 59.5 

Thailand 31.7 27.6 29.5 33.6 35.7 31.6 32.0 30.3 25.5 

United States 11.8 11.2 12.1 14.8 20.6 22.8 24.4 26.6 28.1 29.0 

Venezuela 100.4 87.9 117.7 90.9 35.3 32.3 33.8 44.5 47.6 44.3 

Philippines 43.8 32.0 24.2 24.0 38.8 33.4 37.9 38.1 39.0 

Russian Federation 85.2 99.4 101.3 107.1 113.1 85.3 64.1 75.0 83.3 

Other reporting 

countries 36.0 38.4 42.8 35.5 25.7 28.4 19.1 24.1 28.6 30.6 

All reporting partners 7.1 8.2 10.2 11.8 17.3 17.9 17.5 21.0 22.2 23.5 

Data Source: Calculated by the authors from COMTRADE data of UNSD, all reported exports measured 

at fob price, imports reported at cif price. 

a. Defined in equation (1) of the paper. 

b. Defined in equation (2) of the paper, which is modified from similar index developed by International 

Trade Center at UNCTAD/WTO in Geneva 

c. Defined in equation (3) of the paper, which is modified from similar index developed by International 

Trade Center at UNCTAD/WTO in Geneva 
38

Table 6 Trade Statistics Reported by China, Hong Kong and the United States and Statistical Discrepancies, 1995-2006 (from the US, 

Year 1995 1996 1997 1998 1999 2000 2001 2002 US reported exports to China (fas) + 11,748 11,978 12,805 14,258 13,118 16,253 19,235 22,053 US reported rxports to Hong Kong (fas) + 14,220 13,956 15,115 12,923 12,647 14,625 14,072 12,612 Geographical coverage adjustment for US reported data 

To China - 13 3 4 12 6 15 32 52 To Hong Kong - 14 10 17 11 15 16 18 18 US reported exports to China & Hong Kong (fas) 25,942 25,921 27,899 27,158 25,743 30,847 33,257 34,594 Statistical Discrepancy (Million US dollars) - -725 -660 -2,032 -2,381 153 -1,203 -1,209 -2,966 

cif to fob adjustment for China and Hong Kong reported data 25,217 25,260 25,867 24,777 25,896 29,644 32,048 31,628 China - 419 339 315 378 595 705 790 807 Hong Kong - 381 367 350 304 330 385 346 327 Hong Kong reported re-exports to China for US originated goods - 4,982 5,866 5,965 5,294 5,373 6,109 6,466 6,197 China & Hong Kong reported imports from US (cif) 30,999 31,831 32,496 30,753 32,194 36,843 39,650 38,959 China reported imports from US (cif) + 16,124 16,179 16,301 16,997 19,488 22,365 26,195 27,230 Hong Kong reported imports from US (cif) + 14,876 15,653 16,195 13,756 12,706 14,478 13,456 11,729 

Statistical Descrepency as % of China & Hong Kong reported imports -2.87 -2.61 -7.86 -9.61 0.59 -4.06 -3.77 -9.38 Statistical Descrepency as % of sum of US, China & Hong Kong reported data, ITC consistency indicators (total) -1.42 -1.29 -3.78 -4.58 0.30 -1.99 -1.85 -4.48 

Hong Kong re-export as % of China total imports from US 30.9 36.3 36.6 31.1 27.6 27.3 24.7 22.8 Hong Kong re-export for US as % of Hong Kong total re-export to China 10.0 10.9 10.4 10.1 10.4 9.7 10.2 8.5 

US-China fob/cif 0.962 0.967 0.970 0.968 0.958 0.957 0.960 0.962 US-Hong Kong fob/cif 0.974 0.977 0.978 0.978 0.974 0.973 0.974 0.972 

Data source: All China reported data are from China Customs Authority; all Hong Kong reported data are from Hong Kong Census and Stati

State reported data are from International Trade Commission Oracle database. The data include HS Chapter 1 to 99. 

Note: Geographical adjustments are based on U.S. reported data. China & Hong Kong reported data do not include Virgin Island and Puerto R
39

Table 7. Discrepancy Indexes of Trade Statistics Reported by China, Hong Kong and United States in 

Major HS sections, 1995-2006 (export to China and Hong Kong in percent) 

Year 1995 1996 1997 1998 1999 2000 2001 2002 2003 2004 2005 2006 

Live Animals And Animal Products -29.1 -63.2 -68.2 -76.3 -21.1 -17.3 -5.7 19.0 18.2 4.0 -1.3 -12.6 

Vegetable Products 19.8 3.5 29.8 19.0 20.1 6.2 7.7 -0.8 -28.7 23.1 20.4 0.5 

Animal And Vegetable Fats And Oils 9.5 -76.5 -12.2 -14.6 52.4 41.9 26.4 12.2 -31.1 -124.9 -75.3 -134.8 

Prepared Foodstuffs, Beverages and Tobacco 13.9 2.4 6.0 5.8 13.7 12.8 17.6 19.4 13.6 13.7 0.7 6.2 

Mineral Products 3.2 -16.0 -27.6 1.3 10.6 -6.1 -28.9 26.2 10.3 24.4 21.4 6.1 

Products Of The Chemical Or Allied Industries 4.1 12.1 -4.1 12.2 17.3 9.7 13.3 18.0 25.1 25.2 21.6 19.4 

Plastics And Rubber -7.5 -1.3 -1.4 -3.4 1.8 -13.3 -10.5 -25.0 -23.5 -13.1 -13.2 -17.0 

Raw Hides And Skins, Leather, Fur skins -1.8 9.6 -4.3 2.2 6.9 -31.0 -34.6 -31.8 -36.9 -22.9 -17.0 -19.0 

Wood And Cork Articles -0.7 -3.9 7.9 -6.7 -23.0 -50.2 -67.8 -47.0 -41.0 -49.9 -36.8 -30.3 

Wood Pulp, Paper And Paperboard Articles 9.4 10.8 13.1 5.3 15.5 21.9 13.3 12.0 19.3 21.5 20.4 6.4 

Textiles 2.3 0.4 5.4 -6.1 -9.3 -16.6 -14.4 -35.8 -22.6 6.0 -5.0 -1.4 

Footwear, Headgear And Umbrellas -7.3 -21.6 -4.6 -28.1 -17.2 -27.2 -48.3 -52.2 -18.8 -3.3 -8.9 -8.4 

Articles Of Stone, Plaster, Cement, Ceramic And Glass -6.3 -12.6 -17.9 -19.7 -17.9 -55.1 -33.8 -52.5 -26.6 -21.6 -13.1 -20.2 

Pearls, Precious Stones And Metals -85.3 -50.5 -52.4 -25.5 -26.5 -20.4 -29.3 -13.4 -26.0 -39.7 -48.0 -53.0 

Base Metals -6.5 6.7 3.5 -7.4 2.6 -9.5 -23.6 -34.7 -32.5 -27.6 -55.1 -115.7 

Machinery And Mechanical Appliances 0.9 10.7 -7.0 -1.2 12.9 -2.1 0.4 -0.2 1.1 5.3 7.3 5.9 

Electrical Machinery And Equipment -0.3 -5.6 -4.4 4.2 -3.6 -4.6 2.6 -11.9 -23.3 -9.4 -4.7 -7.0 

Vehicles, Aircraft, Vessels And Other Transport Equipment -17.7 -22.3 -37.3 -84.7 -35.1 -18.9 -26.2 -56.4 -11.7 5.9 -31.8 -16.9 

Medical Instruments, Musical Instruments, Clocks and Watches 7.5 13.7 2.1 0.9 7.4 16.0 8.8 8.5 13.4 15.5 14.1 8.7 

Arms And Ammunition -309.5 -135.3 -150.1 -100.9 -749.9 -1327 -147.1 -229.4 -223.7 -1015. -1487. -332.8 

Miscellaneous Manufactured Articles -15.3 -20.8 -44.2 -47.1 -44.4 -55.9 -62.4 -84.4 -65.6 -61.2 -59.9 -54.2 

Works Of Art, Collectors' Pieces and Antiques -102.4 -94.0 -207.8 -29.6 -53.6 2.5 -26.9 -22.1 36.3 -36.4 10.1 -25.2 

Totalc -1.1 -0.9 -6.5 -7.9 2.2 -2.6 -2.5 -8.4 -6.9 2.8 -2.6 -8.8 

Live Animals And Animal Products -25.4 -48.0 -50.9 -55.2 -19.1 -15.9 -5.6 21.0 20.0 4.1 -1.3 -11.9 

Vegetable Products 22.0 3.6 35.0 21.0 22.3 6.4 8.1 -0.8 -25.1 26.2 22.8 0.5 

Animal And Vegetable Fats And Oils 10.0 -55.3 -11.5 -13.6 71.1 53.1 30.5 13.0 -26.9 -76.9 -54.7 -80.5 

Prepared Foodstuffs, Beverages and Tobacco 14.9 2.5 6.2 6.0 14.7 13.7 19.3 21.5 14.6 14.7 0.7 6.4 

Mineral Products 3.3 -14.8 -24.2 1.3 11.2 -5.9 -25.2 30.2 10.9 27.8 23.9 6.2 

Products Of The Chemical Or Allied Industries 4.2 12.8 -4.0 12.9 18.9 10.2 14.3 19.8 28.6 28.8 24.3 21.4 

Plastics And Rubber -7.3 -1.3 -1.4 -3.3 1.8 -12.5 -9.9 -22.2 -21.0 -12.3 -12.4 -15.7 

Raw Hides And Skins, Leather, Fur skins -1.8 10.1 -4.2 2.2 7.1 -26.8 -29.5 -27.4 -31.2 -20.5 -15.6 -17.4 

Wood And Cork Articles -0.7 -3.8 8.2 -6.5 -20.6 -40.1 -50.6 -38.1 -34.0 -39.9 -31.1 -26.3 

Wood Pulp, Paper And Paperboard Articles 9.8 11.4 14.0 5.5 16.8 24.6 14.3 12.8 21.4 24.1 22.7 6.6 

Textiles 2.4 0.4 5.6 -5.9 -8.9 -15.3 -13.5 -30.4 -20.3 6.2 -4.9 -1.4 

Footwear, Headgear And Umbrellas -7.0 -19.5 -4.5 -24.7 -15.8 -24.0 -38.9 -41.4 -17.2 -3.3 -8.6 -8.1 

Articles Of Stone, Plaster, Cement, Ceramic And Glass -6.1 -11.9 -16.4 -17.9 -16.4 -43.2 -28.9 -41.6 -23.5 -19.5 -12.3 -18.4 

Pearls, Precious Stones And Metals -59.8 -40.3 -41.5 -22.6 -23.4 -18.5 -25.5 -12.6 -23.0 -33.1 -38.7 -41.9 

Base Metals -6.2 7.0 3.6 -7.1 2.6 -9.1 -21.1 -29.6 -27.9 -24.3 -43.2 -73.3 

Machinery And Mechanical Appliances 0.9 11.3 -6.7 -1.2 13.8 -2.0 0.4 -0.2 1.1 5.5 7.5 6.1 

Electrical Machinery And Equipment -0.3 -5.5 -4.3 4.3 -3.5 -4.5 2.7 -11.2 -20.8 -9.0 -4.6 -6.8 

Vehicles, Aircraft, Vessels And Other Transport Equipment -16.2 -20.1 -31.4 -59.5 -29.8 -17.3 -23.2 -44.0 -11.1 6.1 -27.4 -15.6 

Medical Instruments, Musical Instruments, Clocks and Watches 7.8 14.7 2.1 0.9 7.7 17.4 9.2 8.9 14.3 16.8 15.1 9.1 

Arms And Ammunition -121.5 -80.7 -85.7 -67.1 -157.9 -173.8 -84.8 -106.8 -105.6 -167.1 -176.3 -124.9 

Miscellaneous Manufactured Articles -14.2 -18.9 -36.2 -38.1 -36.4 -43.7 -47.5 -59.4 -49.4 -46.9 -46.1 -42.6 

Works Of Art, Collectors' Pieces and Antiques -67.7 -63.9 -101.9 -25.8 -42.3 2.6 -23.7 -19.9 44.4 -30.8 10.6 -22.4 

Totalc -1.1 -0.9 -6.3 -7.6 2.3 -2.5 -2.4 -8.0 -6.7 2.8 -2.6 -8.4 

Data source: All China reported data are from China Customs Authority; all Hong Kong reported data are from Hong Kong 

Census and Statistics Department; all United State reported data are from International Trade Commission Oracle database, 

both exports and imports are measured on fob price. 

a. Defined in equation (1) of the paper. 

b. Defined in equation (2) of the paper, which is modified from similar index developed by International Trade Center at 

UNCTAD/WTO in Geneva. 

c. It includes HS Chapter 1-97.
40

Table 8. Discrepancy Indexes of Trade Statistics Reported by China, Hong Kong and their Major Partners, 1995-2004 

(export to China and Hong Kong, in percent) 

Year 1995 1996 1997 1998 1999 2000 2001 2002 2003 2004 

Statistical Discrepancy as % of China & Hong Kong reported importsa

Argentina -4.3 -25.1 -20.9 5.8 9.9 8.9 8.3 8.1 7.2 17.7 

Australia 2.9 10.8 -6.2 -2.8 3.2 13.3 14.6 16.4 23.6 35.7 

Brazil -5.7 14.8 14.6 9.6 9.1 19.9 10.7 8.6 15.3 32.5 

Canada -6.3 5.5 3.7 15.6 17.8 29.1 25.4 21.0 16.4 23.2 

Chile -19.5 17.1 11.0 1.1 37.8 35.9 21.9 24.7 21.7 11.1 

EU15 -0.9 -6.7 -10.8 -6.5 4.5 8.3 9.2 2.8 3.2 3.2 

EU10 -0.1 26.3 -10.6 -37.2 2.7 -4.4 -0.6 25.8 22.0 10.2 

India -6.3 -6.6 -3.7 2.2 -16.1 -0.8 5.7 -5.9 11.2 17.4 

Indonesia -10.3 -11.6 -0.1 3.9 13.9 16.1 23.8 20.4 23.0 26.2 

Israel -19.8 -35.8 -46.7 -58.2 -56.9 -52.9 -47.5 -42.5 -44.1 -46.2 

Japan -6.1 -4.5 -6.0 -5.3 -2.3 -3.9 1.5 1.0 1.6 2.8 

Korea -22.5 -24.0 -25.3 0.8 -4.8 -1.0 2.1 -1.8 -3.1 0.6 

Malaysia -20.3 -22.2 -4.1 4.2 0.0 10.1 13.4 11.8 18.4 23.1 

Mexico -54.7 6.5 -15.2 -25.1 -7.2 27.4 54.2 43.8 55.2 62.3 

New Zealand -22.7 -10.9 -11.7 1.0 9.4 19.9 10.7 11.2 10.7 8.1 

Norway 11.9 21.1 24.5 18.2 -6.9 46.6 -14.0 6.2 6.7 28.2 

Saudi Arabia 42.5 67.9 71.8 73.4 

Singapore -12.3 -25.4 -35.6 -31.6 -19.8 -21.1 -20.9 -18.9 -21.9 -25.6 

South Africa 30.7 14.6 32.3 40.4 32.2 39.4 31.6 40.9 33.5 47.6 

Switzerland -12.8 -19.1 -18.4 -6.6 -2.9 5.2 10.4 2.4 2.1 6.0 

Thailand -22.8 -22.5 -17.1 -5.2 0.3 6.2 13.9 10.4 15.2 

United States 2.0 1.8 -3.9 -5.1 5.6 1.1 1.0 -2.4 -1.6 7.2 

Philippines 1.2 3.5 1.4 -14.2 19.7 26.6 23.7 35.7 73.9 

Russian Federation 22.9 15.5 18.3 19.1 19.6 50.3 35.8 19.1 30.3 

Other reporting countries -6.1 12.3 -35.6 4.9 1.9 23.7 41.0 35.4 35.8 40.8 

All reporting partners -6.2 -6.2 -10.5 -3.9 0.4 3.8 8.8 4.4 5.5 9.6 

Statistical Discrepancy as % of sum of Partner, China & Hong Kong reported data, ITC consistency indicators (total)b 

Argentina -4.2 -22.3 -18.9 5.9 10.5 9.4 8.7 8.4 7.5 19.5 

Australia 2.9 11.4 -6.0 -2.8 3.2 14.2 15.8 17.9 26.7 43.5 

Brazil -5.6 16.0 15.7 10.1 9.5 22.2 11.3 9.0 16.6 38.8 

Canada -6.1 5.6 3.7 17.0 19.6 34.1 29.1 23.5 17.8 26.3 

Chile -17.8 18.7 11.6 1.1 46.6 43.7 24.6 28.2 24.3 11.7 

EU15 -0.9 -6.5 -10.2 -6.3 4.6 8.6 9.7 2.9 3.3 3.2 

EU10 -0.1 30.2 -10.1 -31.4 2.7 -4.3 -0.6 29.6 24.7 10.8 

India -6.1 -6.4 -3.6 2.2 -14.9 -0.8 5.8 -5.7 11.8 19.1 

Indonesia -9.8 -10.9 -0.1 4.0 15.0 17.6 27.0 22.7 26.0 30.1 

Israel -18.0 -30.4 -37.9 -45.1 -44.3 -41.9 -38.4 -35.1 -36.1 -37.5 

Japan -5.9 -4.4 -5.9 -5.2 -2.3 -3.8 1.5 1.0 1.7 2.8 

Korea -20.3 -21.4 -22.5 0.8 -4.7 -1.0 2.1 -1.8 -3.1 0.6 

Malaysia -18.4 -20.0 -4.0 4.3 0.0 10.6 14.4 12.5 20.2 26.2 

Mexico -42.9 6.7 -14.2 -22.3 -6.9 31.8 74.4 56.1 76.2 90.6 

New Zealand -20.4 -10.3 -11.1 1.0 9.8 22.2 11.3 11.9 11.3 8.5 

Norway 12.7 23.6 28.0 20.0 -6.7 60.8 -13.1 6.4 6.9 32.8 

Saudi Arabia 53.9 102.9 111.9 116.0 

Singapore -11.6 -22.5 -30.2 -27.3 -18.0 -19.1 -18.9 -17.3 -19.7 -22.7 

South Africa 36.3 15.8 38.5 50.6 38.4 49.1 37.5 51.5 40.2 62.5 

Switzerland -12.0 -17.4 -16.9 -6.4 -2.9 5.4 11.0 2.4 2.1 6.2 

Thailand -20.5 -20.3 -15.8 -5.1 0.3 6.4 15.0 11.0 16.4 

United States 2.0 1.9 -3.8 -4.9 5.8 1.1 1.0 -2.4 -1.6 7.5 

Philippines 1.2 3.6 1.4 -13.2 21.8 30.7 26.9 43.4 117.3 

Russian Federation 25.8 16.8 20.2 21.1 21.7 67.2 43.5 21.1 35.7 

Other reporting countries -5.9 13.1 -30.2 5.0 1.9 26.8 51.6 43.1 43.6 51.3 

All reporting partners -6.0 -6.0 -10.0 -3.8 0.4 3.9 9.2 4.5 5.7 10.1 
41

Table 8. Discrepancy Indexes of Trade Statistics Reported by China, Hong Kong and their Major 

Partners, 1995-2004 (export to China and Hong Kong, in percent)—Continued 

Year 1995 1996 1997 1998 1999 2000 2001 2002 2003 2004 

ITC consistency indicators (absolute average)c

Argentina 35.2 36.4 44.7 34.3 27.5 24.4 24.0 22.7 24.3 28.8 

Australia 39.5 48.4 43.9 40.6 35.7 32.3 37.9 36.0 40.7 49.3 

Brazil 24.2 29.6 28.8 27.0 31.8 34.7 31.9 23.0 28.1 43.8 

Canada 25.3 23.0 28.2 34.2 29.1 40.7 37.7 36.0 37.2 36.7 

Chile 28.4 22.1 19.0 27.8 56.5 44.8 29.2 29.5 25.6 13.6 

EU15 13.9 13.7 15.2 14.8 17.3 19.2 20.0 16.0 13.3 13.2 

EU10 70.6 60.7 67.7 68.3 28.3 28.5 23.2 59.5 38.6 27.5 

India 19.7 27.7 21.3 32.6 31.1 29.8 23.1 23.6 28.4 26.8 

Indonesia 20.0 21.4 30.4 32.5 28.5 25.4 33.2 27.2 31.3 34.3 

Israel 26.2 35.7 44.1 49.8 46.3 48.6 56.4 55.0 58.9 47.9 

Japan 10.9 12.0 12.5 11.3 9.8 8.5 7.6 6.9 6.6 7.5 

Korea 23.7 26.2 26.0 25.5 12.9 14.3 18.1 16.9 28.1 33.0 

Malaysia 21.5 24.1 29.1 28.9 14.4 19.6 20.0 19.9 24.8 30.4 

Mexico 108.3 30.9 42.2 49.1 63.5 39.0 85.7 81.0 105.3 110.0 

New Zealand 27.5 23.6 22.6 21.3 28.3 35.0 25.6 28.6 30.8 30.6 

Norway 49.7 59.9 44.0 39.6 39.9 80.7 63.9 20.5 34.1 69.9 

Saudi Arabia 75.6 125.6 115.1 123.7 

Singapore 17.2 24.8 31.8 28.2 18.5 19.7 19.4 18.7 21.1 23.4 

South Africa 65.1 38.5 62.3 73.0 51.6 64.4 45.5 57.9 48.5 66.8 

Switzerland 16.9 23.7 23.9 14.7 10.9 13.4 16.8 13.4 14.1 18.5 

Thailand 25.4 25.4 22.8 27.4 22.8 18.3 20.7 17.4 21.4 

United States 14.9 17.6 15.6 18.6 17.1 12.6 12.7 20.5 21.1 19.1 

Philippines 27.5 29.2 33.1 50.3 31.4 36.4 32.1 47.9 119.5 

Russian Federation 63.4 58.7 51.9 56.8 56.8 74.3 54.6 44.3 48.5 

Other reporting countries 32.5 56.8 39.6 56.6 48.0 43.0 68.3 73.8 61.4 69.2 

All reporting partners 7.6 10.6 11.7 7.5 6.4 8.9 12.0 8.4 9.6 13.3 

Data Source: Calculated by the authors from COMTRADE data of UNSD, all reported exports measured at fob 

price, imports reported at cif price. 

a. Defined in equation (1) of the paper. 

b. Defined in equation (2) of the paper, which is modified from similar index developed by International Trade 

Center at UNCTAD/WTO in Geneva. 

c. Defined in equation (3) of the paper, which is modified from similar index developed by International Trade 

Center at UNCTAD/WTO in Geneva. 
42

Table 9 Decomposition of Discrepancy in Eastbound Trade, 1995 -2005, Millions of U.S. Dollars 

Year 1995 1996 1997 1998 1999 2000 2001 2002 2003 2004 2005 

China reported trade statistics 

Direct exports to U.S. (C1) 9,842 14,057 18,401 22,043 27,087 37,042 39,986 54,104 75,424 105,495 141,943 

Exports to U.S. via Hong Kong (C2) 14,260 12,455 14,106 15,766 14,692 14,632 13,893 15,346 16,296 19,006 20,410 

Exports to U.S. via third countries (C3) 611 196 209 156 236 453 388 494 745 410 459 

Hong Kong reported trade statistics 

Domestic exports to U.S. (C4) 7,884 6,925 7,082 7,064 6,611 6,984 6,099 5,368 5,020 4,955 4,850 

Re-exports to U.S. for China (C5) 27,568 29,172 31,236 30,853 31,962 36,416 33,246 34,303 33,392 35,504 38,268 

Sum of Hong Kong Based flows(C2+C4+C5) 49,712 48,552 52,424 53,684 53,266 58,032 53,237 55,017 54,708 59,464 63,528 

U.S. shipping data for imports from China 

Direct imports from Chinese ports (U1) 11,573 15,119 21,613 28,124 36,290 48,844 53,502 73,343 99,996 138,387 178,426 

Re-exports to U.S. via Hong Kong (U5) 24,802 27,287 31,035 32,155 34,051 39,010 35,554 37,503 35,611 38,612 42,770 

Transshipment via Hong Kong (U2) 7,800 7,647 8,033 8,543 8,676 10,702 10,295 10,262 11,045 11,920 12,294 

Indirect imports via third countries (U3) 1,678 1,772 2,334 2,775 3,029 3,391 3,511 4,727 6,289 8,620 11,099 

Total imports from China 45,853 51,824 63,015 71,597 82,047 101,947 102,861 125,835 152,942 197,538 244,589 

U.S. reported trade statistics 

Imports from Hong Kong (U4) 9,801 9,375 9,712 10,001 9,898 10,697 9,025 8,708 8,248 8,682 8,128 

U.S. geographical adjustment for China (U6) 106 132 145 151 195 216 256 299 369 414 510 

U.S. geographical adjustment for Hong Kong (U7) 36 67 50 60 43 35 24 18 24 24 27 

Sum of Hong Kong Based flows(U2+U4+U5-U7) 42,367 44,241 48,730 50,639 52,582 60,374 54,850 56,456 54,881 59,189 63,165 

 

Discrepancies in direct trade (C1-U1) 1,731 1,062 3,212 6,082 9,203 11,802 13,516 19,240 24,572 32,891 36,484 

Discrepancies in re-exports (C5-U5) -2,766 -1,886 -201 1,301 2,089 2,594 2,308 3,200 2,219 3,109 4,501 

Discrepancies in transshipment (C2-U2) -6,460 -4,808 -6,073 -7,223 -6,016 -3,930 -3,598 -5,084 -5,252 -7,086 -8,116 

Discrepancies in H.K. domestic exports (C4-U4) 1,917 2,450 2,630 2,937 3,287 3,713 2,927 3,340 3,229 3,727 3,279 

Discrepancies in trade via third Countries (C3-U3) 1,067 1,575 2,125 2,619 2,793 2,937 3,123 4,233 5,544 8,210 10,640 

Discrepancies in sum of Hong Kong based flows -7,346 -4,311 -3,694 -3,045 -683 2,343 1,613 1,438 172 -275 -362 

 

China & Hong Kong reported exports to U.S. 60,165 62,805 71,034 75,882 80,589 95,527 93,611 109,615 130,878 165,369 205,929 

U.S. reported imports from China & Hong Kong 55,511 61,000 72,532 81,387 91,707 112,393 111,607 134,227 160,797 205,781 252,181 

Total discrepancy a

 -4,654 -1,805 1,498 5,504 11,118 16,866 17,997 24,612 29,920 40,412 46,252 

Statistical Discrepancy as % of U.S. reported imports 

Total -8.38 -2.96 2.07 6.76 12.12 15.01 16.12 18.34 18.61 19.64 18.34 

Direct trade 14.96 7.03 14.86 21.62 25.36 24.16 25.26 26.23 24.57 23.77 20.45 

Hong Kong re-exports -11.15 -6.91 -0.65 4.05 6.14 6.65 6.49 8.53 6.23 8.05 10.52 

Hong Kong transshipment -82.82 -62.88 -75.60 -84.56 -69.35 -36.73 -34.95 -49.54 -47.55 -59.45 -66.01 

Hong Kong domestic exports 19.56 26.13 27.08 29.37 33.21 34.71 32.43 38.35 39.14 42.93 40.34 

Sum of Hong Kong Based flows -17.34 -9.74 -7.58 -6.01 -1.30 3.88 2.94 2.55 0.31 -0.46 -0.57 

Statistical Discrepancy as % of average of U.S., China & Hong Kong reported data 

Total -8.05 -2.92 2.09 7.00 12.91 16.22 17.54 20.19 20.52 21.78 20.19 

Direct trade 16.17 7.28 16.05 24.25 29.04 27.48 28.92 30.19 28.02 26.97 22.78 

Hong Kong re-exports -10.56 -6.68 -0.65 4.13 6.33 6.88 6.71 8.91 6.43 8.39 11.11 

Hong Kong transshipment -58.57 -47.84 -54.86 -59.43 -51.49 -31.03 -29.75 -39.71 -38.42 -45.83 -49.63 

Hong Kong domestic exports 21.68 30.06 31.32 34.42 39.82 42.00 38.70 47.45 48.67 54.66 50.53 

Sum of Hong Kong Based flows -15.95 -9.29 -7.30 -5.84 -1.29 3.96 2.98 2.58 0.31 -0.46 -0.57 

Source: US Census Bureau. a. The total discrepancy is the difference between the two rows above. “China and Hong Kong reported exports to 

U.S.” is the sum of C1-C5. “U.S. reported imports from China and Hong Kong” is the sum of U1-U5 minus the two geographical adjustments, U6 

and U7. These reflect U.S. imports in the customs districts of Puerto Rico and the Virgin Islands, which are treated as destinations separate from 

the United States in China and Hong Kong data. The data exclude HS Chapter 98 and 99. 
43

Table 10 Percentage of Each Component in Total Reported East Bound Trade, 1995-2005 

Year 1995 1996 1997 1998 1999 2000 2001 2002 2003 2004 2005 

Share in adjusted China and Hong Kong reported totala 

Direct exports to U.S. 16.07 21.83 25.15 28.08 32.49 37.62 41.34 47.52 55.29 60.78 65.54 

Re-exports to U.S. for China 45.02 45.31 42.70 39.30 38.33 36.98 34.37 30.13 24.48 20.45 17.67 

Exports to U.S. via Hong Kong 23.29 19.35 19.28 20.08 17.62 14.86 14.36 13.48 11.95 10.95 9.42 

Domestic exports to U.S. 12.88 10.76 9.68 9.00 7.93 7.09 6.30 4.72 3.68 2.85 2.24 

Exports to U.S. via third countries 2.74 2.75 3.19 3.53 3.63 3.44 3.63 4.15 4.61 4.97 5.13 

Share in U.S. reported total 

Direct imports from ports within China 20.79 24.71 29.72 34.47 39.47 43.36 47.82 54.51 62.04 67.11 70.60 

Re-exports to U.S. via Hong Kong 44.56 44.59 42.67 39.41 37.03 34.63 31.78 27.87 22.09 18.72 16.92 

Transshipment to U.S. Via Hong Kong 14.02 12.49 11.04 10.47 9.44 9.50 9.20 7.63 6.85 5.78 4.86 

Imports from Hong Kong (fob) 17.61 15.32 13.35 12.26 10.77 9.50 8.07 6.47 5.12 4.21 3.22 

Indirect imports via third countries 3.01 2.89 3.21 3.40 3.29 3.01 3.14 3.51 3.90 4.18 4.39 

Hong Kong re-export plus transshipment share

As % of China and Hong Kong total exports to 

U.S. 73.69 67.48 62.93 58.33 54.13 49.57 45.40 38.80 30.69 25.18 21.24 

As % in U.S. shipping data 54.22 52.79 49.36 45.01 41.60 38.35 34.65 29.87 23.34 19.59 17.52 

a. The adjustment here made is to replace China’s reported exports through third countries with U.S.-reported 

data, as the extent of the underreporting is so severe. 

Table 11. Descriptive Statistics 

Mean Standard 

Deviation 

Minimum Maximum 

Dependent variable 

 Discrepancy (ER) 7.71 24.14 -90.94 97.60 

Independent variable 

 Processing trade export share 37.44 31.69 0 99.98 

 State-owned enterprise export share 53.48 25.74 2.41 100.00 

 Hong Kong re-export share 21.61 21.94 0 89.56 

 Hong Kong domestic export share 4.84 12.23 0 89.30 

 U.S. import share passing through third 

 Countries 5.94 8.90 0 82.46 

 U.S. re-export as a share of U.S. imports 3.99 4.80 0 44.78 

 Time (years since 1995) 3.50 2.87 1 10 

 Valuation (share of goods with no unit values) 9.83 19.71 0 99.99 

 Homogeneity index 11.64 11.12 1.02 63.51 

 U.S. tariff, ad valorem percent 3.75 3.85 0 32.07 

Memo: Mean for normal trade = 61.22 Mean for foreign-invested enterprises = 37.12 
44

Table 12 Regression results – OLS specifications 

Dependent variable – Discrepancy index(ER) N = 960 (910 without outliers) 

 (1) (2) (3) (4) 

Processing trade -.673*** - .028 -.565*** .140*** 

export share (.052) (.049) (.051) (.040) 

State-owned enterprise .192** -.050 -.040 -.077*** 

export share (.075) (.068) (.072) (.054) 

Hong Kong .534*** .041 .303*** -.359*** 

Re-export share (.078) (.057) (.078) (.048) 

Hong Kong domestic -.008 .130 .115 .288*** 

export share (.122) (.086) (.114) (.069) 

U.S. import share .331** -.007 .359 -.798*** 

passing through (.166) (.251) (.163) (.222) 

third countries 

U.S. re-exports as -.610* -.730*** -1.419*** -.812*** 

share of U.S. imports (.333) (.203) (.404) (.168) 

Time 2.857*** 1.861*** 2.056*** 1.241*** 

 (.589) (.358) (.567) (.288) 

Valuation problems .279*** .200*** .655*** .331*** 

 (.083) (.037) (.103) (.032) 

 

Homogeneity -.087 -.228 .162 .593*** 

 (.139) (.153) (.140) (.153) 

U.S. import tariffs -2.376*** -1.195*** -2.355** -0.673*** 

 (.403) (.261) (.412) (.220) 

R2 .2576 .2185 .2344 .3951 

Data weighted? No Yes No Yes 

Outliers? Included Included Excluded Excluded 

Standard errors in parentheses *** significant at .01, ** at .05 and * at .10. Intercept not 

reported. 
45

Table 13 Regression results- Fixed effects 

Dependent variable – Discrepancy index (ER) N = 960 (910 without outliers) 

 (1) (2) 

Processing trade -.304*** -.320*** 

export share (.074) (.075) 

State-owned enterprise -.003 .023 

export share (.065) (.075) 

Hong Kong .348*** .321*** 

re-export share (.106) (.110) 

Hong Kong domestic .423*** .419*** 

export share (.140) (.140) 

U.S. import share .606*** .584*** 

passing through (.140) (.142) 

third countries 

U.S. re-exports as -.835* -.326 

share of U.S. imports (.444) (.582) 

Time 2.755*** 2.441*** 

 (.453) (.474) 

Valuation problems .377 .705* 

 (.309) (.374) 

Homogeneity -.044 .091 

 (.370) (.388) 

U.S. import tariffs .118 -1.233 

 (.796) (.1.140) 

R2 .7710 .7255 

Data weighted? No No 

Outliers? Included Excluded 

HS fixed effects? Yes No 

Standard errors in parentheses *** significant at .01 ** significant at .05 

* significant at .10. 
46

Appendix Table: Concordance between Major HS section and HS Chapters 

HS Section Code 

HS Section Code Description Corresponding HS Chapters and Descriptions 

01 Live animals and animal 

products 

01 live animals 02 meat and edible meat offal 03 fish and crustaceans, mollusks and other aquatic invertebrates 04 dairy produce, birds' eggs, natural honey and edible products of animal origin not elsewhe

05 products of animal origin not elsewhere specified or included 

02 Vegetable products 06 live trees and other plants, bulbs and roots, cut flowers and ornamental foliage 

07 edible vegetables and certain roots and tubers 08 edible fruit and nuts, peel of citrus fruit or melons 09 coffee, tea, mate and spices 10 cereals 11 milling industry products, malt, starches, insulin and wheat gluten 12 oil seeds and oleaginous. fruits, miscellaneous grains, seeds and fruits, industrial or medic

fodder 13 lac, gums, resins and other vegetable saps and extracts 14 vegetable plaiting materials and vegetable products, not elsewhere specified or included 

03 Animal and vegetable fats 

and oils, cleavage products and waxes 

15 animal or vegetable fats and oils and their cleavage products, prepared edible fats, animal 

04 Prepared foodstuffs, 

beverages, spirits, vinegar, and tobacco 

16 edible preparations of meat, fish, crustaceans, mollusks or other aquatic invertebrates 

17 sugars and sugar confectionery 18 cocoa and cocoa preparations 19 preparations of cereals, flour, starch or milk, bakers' wares 20 preparations of vegetables, fruit, nuts, or other parts of plants 

21 miscellaneous edible preparations 22 beverages, spirits and vinegar 23 residues and waste from the food industries, prepared animal feed 

24 tobacco and manufactured tobacco substitutes 

05 Mineral products 25 salt, sulfur, earths and stone, plastering materials, lime and cement 

26 ores, slag and ash 27 mineral fuels, mineral oils and products of their distillation, bituminous substances, minera

06 Products of the chemical 

or allied industries 

28 inorganic chemicals, organic or inorganic compounds of precious metals, of rare-earth met

or of isotopes 29 organic chemicals 30 pharmaceutical products 31 fertilizers 32 tanning or dyeing extracts, tannins and derivatives, dyes, pigments and other coloring matputty and other mastics, inks 33 essential oils and resinoids, perfumery, cosmetic or toilet preparations 34 soap etc., lubricating products, waxes, polishing or scouring products, candles etc., modeland dental plaster preparations 
47

HS Section Code 

HS Section Code Description Corresponding HS Chapters and Descriptions 

06—cont.

Products of the chemical or allied industries 

35 albuminoidal substances, modified starches, glues, enzymes 36 explosives, pyrotechnic products, matches, pyrophoric alloys, certain combustible pre37 photographic or cinematographic goods 38 miscellaneous chemical products 

07 Plastics and rubber 39 plastics and articles thereof 

40 rubber and articles thereof 

08 Raw hides and skins, leather, 

fur skins , saddlery and handbags 

41 raw hides and skins (other than fur skins) and leather 42 articles of leather, saddlery and harness, travel goods, handbags and similar containethan silkworm gut) 43 fur skins and artificial fur, manufactures thereof 

09 Wood and cork articles 44 wood and articles of wood, wood charcoal 

45 cork and articles of cork 46 manufactures of straw, esparto or other plaiting materials, basketware and wickerwork 

10 Wood pulp, paper and 

paperboard articles 

47 pulp of wood or other fibrous cellulosic material, recovered (waste and scrap) paper a48 paper and paperboard, articles of paper pulp, paper or paperboard 49 printed books, newspapers, pictures and other printed products, manuscripts, typescr

11 Textiles 50 silk, including yarns and woven fabrics thereof 

51 wool and fine or coarse animal hair, including yarns and woven fabrics thereof, horseh

52 cotton, including yarns and woven fabrics thereof 

53 vegetable textile fibers not elsewhere specified or included, yarns and woven fabrics onot elsewhere specified or included and paper 54 manmade filaments, including yarns and woven fabrics thereof 55 manmade staple fibers, including yarns and woven fabrics thereof 

56 wadding, felt and nonwovens, special yarns, twine, cordage, ropes and cables and art57 carpets and other textile floor coverings 58 special woven fabrics, tufted textile fabrics, lace, tapestries, trimmings, embroidery 59 impregnated, coated, covered or laminated textile fabrics, textile articles suitable for in

60 knitted or crocheted fabrics 61 articles of apparel and clothing accessories, knitted or crocheted 62 articles of apparel and clothing accessories, not knitted or crocheted 

63 made-up textile articles not elsewhere specified or included, needlecraft sets, worn clo

articles, rags 

12 Footwear, headgear, 

umbrellas, walking sticks, whips, feathers, artificial flowers 

64 footwear, gaiters and the like, parts of such articles 65 headgear and parts thereof 66 umbrellas, sun umbrellas, walking-sticks, seat-sticks, whips, riding-crops and parts the

67 prepared feathers and down and articles thereof, artificial flowers, articles of human h

13 Articles of stone, plaster, 

cement, asbestos, mica, ceramic, and glass 

68 articles of stone, plaster, cement, asbestos, mica or similar materials 69 ceramic products 70 glass and glassware 

HS Section 

HS Section Code Description Corresponding HS Chapters and Descriptions 
48

Code 14 Natural and cultured pearls, 

precious and semiprecious stones, precious metals and coin 

71 natural or cultured pearls, precious or semiprecious stones, precious metals, precious thereof, imitation jewelry, coin 

15 Base metals 72 iron and steel 

73 articles of iron or steel 74 copper and articles thereof 75 nickel and articles thereof 76 aluminum and articles thereof 78 lead and articles thereof 79 zinc and articles thereof 80 tin and articles thereof 81 base metals not elsewhere specified or included, cermets, articles thereof 82 tools, implements, cutlery, spoons and forks, of base metal, parts thereof of base met83 miscellaneous articles of base metal 

16 Machinery And Mechanical 

Appliances, Nuclear Reactors And Boilers 

84 Nuclear Reactors, Boilers, Machinery And Mechanical Appliances, Parts Thereof 

17 Electrical machinery and 

equipment, sound recorders, television image recorders 

85 electrical machinery and equipment and parts thereof, sound recorders and reproduceand reproducers, parts and accessories 

18 Vehicles, aircraft, vessels and 

transport equipment 

86 railway or tramway locomotives, rolling stock, track fixtures and fittings, and parts ther

signal equipment of all kinds 87 vehicles, other than railway or tramway rolling stock, and parts and accessories thereo88 aircraft, spacecraft, and parts thereof 89 ships, boats and floating structures 

19 Optical, cinematographic, 

measuring, precision, medical instruments, clocks and watches, musical instruments 

90 optical, photographic, cinematographic, measuring, checking, precision, medical or su

apparatus, parts and accessories thereof 91 clocks and watches and parts thereof 92 musical instruments, parts and accessories thereof 

20 Arms and ammunition 93 arms and ammunition, parts and accessories thereof 21 Miscellaneous manufactured 

articles 

94 furniture, bedding, cushions etc., lamps and lighting fittings not elsewhere specified or signs, nameplates and the like, prefabricated buildings 95 toys, games and sports equipment, parts and accessories thereof 96 miscellaneous manufactured articles 

22 Works of art, collectors' pieces 

and antiques 

97 works of art, collectors' pieces and antiques