1

Transportation of 

U.S. Grains

A Modal Share Analysis 

1978-2007

United States

Department of

Agriculture

Agricultural 

Marketing

Service

April 2011
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and employer.
i

Transportation of 

U.S. Grains

A Modal Share Analysis 

1978-2007

Nick Marathon, Economist

Marina R. Denicoff, Economist

Transportation Services Division

USDA Agricultural Marketing Service
ii

Abstract

This report analyzes the movements of corn, wheat, soybeans, sorghum, and barley to either the 

domestic market or U.S. ports for export between 1978 and 2007. It is the fi fth update of the initial 

modal share study completed in 1992. The purpose of this series of reports is to provide information 

about changes and trends in the relative competitiveness and effi ciencies among the modes in moving 

grain. As a result of analyzing secondary data sources, estimates of the tonnages of grain railed, barged, 

and trucked are then used to calculate the modal shares of each commodity and all grains. The modal 

shares can be applied to analyzing the transportation implications due to changes in grain production and 

demand for U.S. grain domestically and overseas.
iii

Contents

Introduction 1

Methodology 2

 Estimating modal tonnages and shares 2

 Estimating surplus-defi cit areas 3

Grain Modal Shares From 1978 to 2007 7

Corn Modal Shares 10

 Corn Supply and Demand 13

 Corn Transportation Characteristics 14

Wheat Modal Shares 16

 Wheat Supply and Demand 18

 Wheat Transportation Characteristics 19

Soybean Modal Shares 20

 Soybean Supply and Demand 23

 Soybean Transportation Characteristics 24

Exports By Port Area 25

 Corn Exports by Port Area 27

 Wheat Exports by Port Area 28

 Soybean Exports by Port Area 29

Conclusion 30

Bibliography 31

Appendix A: Modal Share Methodology 32

Appendix B: FIPS Regions Included in Rail Export Tonnages 34

Appendix C: Port Areas and Major City Ports 35

Appendix D: Modal Share Information for Other Crops 36
iv

Figures

Figure 1: Estimating modal tonnages and share 2

Figure 2: Total grain movements to domestic and export markets, 1978-2007 4

Figure 3: U.S. grain shipments by commodity, 1978-2007 4

Figure 4: U.S. corn, soybeans, and wheat production, 1978-2009 6

Figure 5: U.S. grain modal shares, 1978-2007 7

Figure 6: U.S. corn domestic shipments by mode, 1995–2007 12

Figure 7: U.S. corn export shipments by mode, 1995–2007 12

Figure 8: Corn surplus/defi cit map with the transportation system 14

Figure 9: U.S. wheat domestic shipments by mode, 1995–2007 17

Figure 10: U.S. wheat export shipments by mode, 1995-2007 17

Figure 11: Wheat surplus/defi cit map with the transportation system 19

Figure 12: U.S. soybean domestic shipments by mode, 1995–2007 22

Figure 13: U.S. soybean export shipments by mode, 1995–2007 22

Figure 14: Soybean surplus/defi cit map with the transportation system 24

Figure 15: Port share of grain exports, 1983–2009 25

Figure 16: Port share of corn exports, 1983–2009 27

Figure 17: Port share of wheat exports, 1983–2009 28

Figure 18: Port share of soybean exports, 1983–2009 29

Figure 19: U.S. sorghum domestic shipments by mode, 1995–2007 37

Figure 20: U.S. sorghum export shipments by mode, 1995–2007 37

Figure 21: U.S. barley domestic shipments by mode, 1995–2007 39

Figure 22: U.S. barley export shipments by mode, 1995–2007 39
v

Tables

Table 1: Tonnages of U.S. grains transported, by type of crop and type of movement, 

 1995–2007 5

Table 2: Tonnages and modal shares for all U.S. grains, 1995–2007 8

Table 3: Modal Share Summary: 2007 and 5-year average, percent 9

Table 4: Tonnages and modal shares for U.S. corn, 1995–2007 11

Table 5: Corn usage by sector, percentage 13

Table 6: U.S. corn supply and use for various marketing years, million bushels 13

Table 7: Tonnages and modal shares for U.S. wheat, 1995-2007 16

Table 8: U.S. wheat supply and use for various marketing years, million bushels 18

Table 9: Tonnages and modal shares for U.S. soybeans, 1995-2007 21

Table 10: U.S. soybean supply and use for various marketing years, million bushels 23

Table 11: Tonnages and modal shares for U.S. sorghum, 1995–2007 36

Table 12: Tonnages and modal shares for U.S. barley, 1995–2007 38
vi
1

Introduction

The purpose of this analysis is to examine trends in the type of transportation used to move grains 

grown for the food and feed industry.1 Grains produced in the United States move to domestic and 

foreign markets through a well-developed transportation system. Barge, rail, and truck transpor tation 

facilitate a highly competitive market that bridges the gap between U.S. grain producers and domestic and 

foreign consumers.

Barges, railroads, and trucks often compete head-to-head to supply trans portation for grains. Despite a 

high degree of competition in some markets, these modes also complement each other. Before a bushel 

of grain reaches its fi nal destination, it has often been transported by two or more modes. This balance 

between competition and integration provides grain ship pers with a highly effi cient, low-cost system of 

transportation. The competitive ness of U.S. grains in the world market and the fi nancial well-being of U.S. 

grain producers depends upon this competitive balance. A highly competitive and effi cient transportation 

system results in lower shipping costs, smaller marketing margins for middlemen, and more competitive 

export prices. Such effi ciencies also result in lower food costs for U.S. consumers and higher market 

prices for U.S. producers.

This analysis of the transportation of the fi nal movement of grain, by mode, provides information about 

changes in market share among the modes. Over several years, such work helps identify critical trends 

affecting the transportation of grain. It also provides a framework to assess public policies that infl uence 

the development and success of the Nation’s transportation infrastructure. Public policies that promote an 

effi cient grain transportation system also promote strong U.S. agricultural and rural economies.

1 For this analysis, it is assumed that corn, wheat, soybeans, sorghum, and barley represent all grain movements. 
2

Estimating modal tonnages and shares

Any effort to measure tonnages of grain moved by mode of transport is limited by the absence of 

information on the total volume of truck movements. Accurate data exist for barge and rail freight 

tonnages and commodities, but not for trucks. Other analyses of grain movements have relied extensively 

on survey data to overcome this obstacle. This analysis uses the Waterborne Commerce Statistics of the 

U.S. Army Corps of Engineers to calculate tonnages of barged grain and uses the Carload Waybill Sample 

from the Surface Transportation Board to estimate the amount of railed grain. Trucking data are derived 

from known grain production data, as compared to the estimates of the railed and barged volumes of 

grain. Estimating these modal grain volumes and modal shares on an annual basis provides a data series 

that tracks changes in grain transportation over time.

In this analysis, the term “modal share” describes that portion of the total tonnages of grain moved by 

each mode of transport—barge, rail, or truck. These shares, expressed as percentag es, were determined 

by mode for particular types of grains and movements. Grains identifi ed for this analysis were corn, 

wheat, soy beans, sorghum, and barley. The 1992 and 1998 versions of this study also included rye 

and oats. Rye and oats were taken out of the calculations for this report because of unreliability due to 

small volumes, which total less than 1 percent of all grain movements. Transport modes are categorized 

according to the fi nal movement going to do mestic markets or ports for export.

The estimates of modal tonnages and shares are based on the amount of grain moved to commercial 

markets. Truck ton nages are estimated by subtracting barge and rail tonnages from total tonnages 

transport ed. Figure 1 shows how modal shares are estimated. For each crop, total movements are 

determined fi rst, and then exports are subtracted from the total to get domestic movements. Total rail 

and barge volumes are subtracted from total movements to get truck movements. A more detailed 

description of the methodology is covered in Appendix A.

Methodology

Figure 1: Estimating modal tonnages and share

Total 

Movements*

Domestic 

Truck

Domestic 

Barge

Domestic 

Rail

Export 

Truck

Export 

Barge

Export 

Rail

Total 

Truck

Total 

Barge

Total 

Rail

Domestic 

Movements

Export 

Movements

(=)

(-) 

 KEY

 Subtract 

 Equals

 *Total movement equals total 

 disappearance less the amount of 

 grain grown and used on farm.

(=)

(-)

(=) (=)

(=)

(=)

(=)

(-)

(-)

(-)

(-)

(-)

(-) (-)

(-)
3

Estimating surplus-defi cit areas

Surplus-defi cit areas show the difference between production and consumption. The transportation 

system overlaid with the surplus-defi cit production maps, along with the location of the key ports, provides 

a clear visual representation of the importance of grain transportation. The fi rst step in estimating 

surplus-defi cit areas is to calculate production and consumption by a given geography. The maps in this 

study were created using USDA-NASS data for county production of corn, soybeans, and wheat. Corn 

and soybean consumption levels were calculated by applying a conversion factor (grain-consuming animal 

unit (GCAU) and high protein animal unit (HPAU)) to the 2007 Census of Agriculture animal inventories 

by county and the feed use in 2007. In the case of wheat, U.S. consumption was divided by county 

population and subtracted from county wheat production as reported by NASS. 

Grain Tonnages Moved. The amount of grain moved in a given calendar year is infl uenced by grain 

production trends. A large crop will generate a large transportation requirement, either in the year 

harvested or subsequent years. The fi rst movement from the farm is almost always by truck; additional 

movements may be by one or more modes. This analysis estimates the mode of the fi nal movement of 

grain shipments. 

From 1978 to 2007, the trucking sector experienced the largest growth among modes of grain 

movements. Truck tonnages increased from 74 million to 245 million tons—growing at a compound 

annual growth rate (CAGR) of 4.2 percent. During this period, rail movements increased from 117 million 

to 153 million tons (0.9 percent CAGR), and barge movements from 51 million to 66 million tons (0.9 

percent CAGR).

A remarkable trend in grain transportation is the nearly constant annual increases in the amount of grain 

transported each year (Figure 2). Total grain movements increased 92 percent from 1978 to 2007. During 

those 30 years, there were only 8 years in which annual grain movements decreased. The decreases in 

1989 and 1994 are notable. The decline in 1989 refl ected the previous year’s production losses due to 

the widespread drought in the Midwest in 1988. The decrease in 1994 was again caused by the previous 

year’s production losses, but this time the loss was caused by massive fl ooding in 1993. Grain movements 

are divided into two distinct categories—domestic and export. From 1978 to 1982, exports made up 

about 50 to 55 percent of all grain movements. By 2007, exports had dropped to 30 percent of all grain 

movements. U.S. grain exports have not seen signifi cant growth since the 1980’s. The increase in the 

world’s supply from other exporting countries has held U.S. export levels relatively steady. 

There has been signifi cant domestic growth in corn-based industrial products, with ethanol being the 

biggest growth market. Other industrial uses with growth potential include plastics, solvents and 

packaging. Figure 3 shows the annual movements by commodity and the marked increase in annual 

corn shipments.
4

Figure 2: Total grain movements to domestic and export markets, 1978-2007

Figure 3: U.S. grain shipments by commodity, 1978-2007

0

50

100

150

200

250

300

350

400

450

500

197819801982198419861988199019921994199619982000200220042006

Million Tons

Year

Exports

Domestic

Total

0

50

100

150

200

250

300

350

400

450

500

1978 1980 1982 1984 1986 1988 1990 1992 1994 1996 1998 2000 2002 2004 2006

Million Tons

Year

Corn Wheat

Soybeans Sorghum

Barley Total
5

In 2007, corn shipments represented 63 percent of all grain movements; movements of soybeans and 

wheat were 19 percent and 14 percent, respectively. Combined, corn, soybeans, and wheat make up 

96 percent of all grain transportation tonnages. For this analysis, the remaining 4 percent consists of 

sorghum and barley. Movements of total, export, and domestic grain movements from 1995 to 2007 are 

shown in Table 1.

Table 1: Tonnages of U.S. grains transported, by type of crop and type of movement, 

1995–2007 

Year

Corn Wheat Soybeans Sorghum Barley All grains

1,000 tons

Total

1995 217,515 64,583 70,492 15,118 9,394 377,102

1996 194,804 68,764 69,269 16,632 8,941 358,409

1997 207,856 64,099 73,549 19,031 8,241 372,775

1998 209,977 68,859 76,848 14,114 7,345 377,142

1999 223,875 69,223 77,501 15,112 6,993 392,703

2000 229,346 69,908 78,656 14,554 7,317 399,781

2001 237,837 64,470 85,347 12,446 6,691 406,792

2002 233,925 58,659 85,367 11,508 5,752 395,211

2003 235,846 64,789 84,792 11,018 5,419 401,865

2004 241,267 66,863 72,735 10,910 5,267 397,043

2005 260,166 62,358 79,488 10,315 5,270 417,598

2006 285,225 57,966 87,636 9,299 4,832 444,958

2007 290,576 66,952 89,405 11,617 5,547 464,098

Export

1995 65,200 35,515 24,760 6,103 1,368 132,946

1996 57,195 35,420 25,840 5,525 1,216 125,196

1997 45,995 28,960 26,340 5,768 1,768 108,831

1998 44,865 30,070 25,450 5,507 656 106,548

1999 57,820 33,130 25,509 6,309 704 123,472

2000 52,957 31,780 29,698 7,037 1,128 122,600

2001 53,032 29,410 31,663 6,720 944 121,769

2002 52,329 27,580 30,506 6,085 552 117,052

2003 47,607 29,390 33,989 5,546 684 117,217

2004 53,373 34,710 27,710 5,089 370 121,252

2005 50,629 30,390 28,118 5,060 839 115,036

2006 63,428 26,790 31,063 5,249 440 126,969

2007 63,470 37,080 32,823 6,394 833 140,601

Domestic

1995 152,315 29,068 45,732 9,015 8,026 244,156

1996 137,609 33,344 43,429 11,106 7,725 233,213

1997 161,861 35,139 47,209 13,263 6,473 263,945

1998 165,111 38,789 51,398 8,607 6,689 270,594

1999 166,055 36,093 51,992 8,803 6,289 269,231

2000 176,389 38,128 48,959 7,516 6,189 277,181

2001 184,805 35,060 53,685 5,726 5,747 285,023

2002 181,596 31,079 54,861 5,422 5,200 278,159

2003 188,240 35,399 50,802 5,472 4,734 284,648

2004 187,894 32,153 45,026 5,822 4,897 275,790

2005 209,537 31,968 51,370 5,256 4,431 302,562

2006 221,797 31,176 56,573 4,051 4,392 317,989

2007 227,106 29,872 56,582 5,223 4,714 323,497
6

The constant growth in annual grain shipments is partly due to the remarkable increase in annual corn 

production. Figure 4 shows that corn production increased from 7.3 billion bushels in 1978 to 13.1 billion 

bushels in 2009. During the same period, soybean production ranged from 1.5 to 3.4 billion bushels per 

year and wheat production ranged from 1.6 to 2.8 billion bushels per year. Corn and soybeans had record 

crops in 2009, whereas wheat set a production record in 1981.

Emerging markets for grain have created new transportation patterns. One of the most prominent 

market growths has occurred in the ethanol industry. This renewable fuel has increased the use of corn 

domestically and created a growing market for distillers grains—a co-product of ethanol production used 

as animal feed. The ethanol industry produced 6.5 billion gallons in 2007, up from 175 million gallons 

produced in 1980.2 USDA projects the use of corn for ethanol in 2009/10 to reach 4.8 billion bushels—

more than 2.5 times the expected corn exports that year, and up from 3.0 billion bushels in 2007. Trucks 

are the primary mode of transportation of corn to ethanol biorefi neries, but the newer and larger facilities 

are able to receive unit trains of corn, increasing the importance of grain rail service to ethanol plants.

2 U.S. Energy Information Administration, U.S. Department of Energy

Figure 4: U.S. corn, soybeans, and wheat production, 1978-2009

Source: National Agricultural Statistics Service, USDA

0

2

4

6

8

10

12

14

1978198019821984198619881990199219941996199820002002200420062008

Billion Bushels

Corn

Soybeans

Wheat
7

The most signifi cant trend in a single mode of moving grain was the overwhelming increase in the volume 

of grain moved by trucks. In terms of percent of total movements, the truck share became the dominant 

mode in 1993; since then its share has been increasing over rail and barge. Since 1993, truck has been 

the primary transporter of grain, followed by rail and then barge. The use of trucks to transport grain 

allows farmers the fl exibility of delivering their products to different markets. With new markets, such as 

local ethanol facilities, the farmer has more options for selling grain to maximize profi ts. During the study 

period, rail and barge experienced a downward trend in each mode’s share of total grain shipments (Figure 

5). Truck use increased from 31 percent in 1978 to 53 percent of all movements in 2007. The share of 

rail movements decreased from 48 to 33 percent, while barge decreased from 21 to 14 percent. Table 2 

shows the tonnages and modal share of grains from 1995 to 2007.

Figure 5: U.S. grain modal shares, 1978-2007

0%

10%

20%

30%

40%

50%

60%

197819791980198119821983198419851986198719881989199019911992199319941995199619971998199920002001200220032004200520062007

Percentage of total grain movements

Year

Rail Barge Truck

Grain Modal Shares From 1978 to 2007
8

Table 2: Tonnages and modal shares for all U.S. grains, 1995–2007

Year & 

type of 

movement

Mode of transport

Rail Barge Truck

1,000 tons Percent 1,000 tons Percent 1,000 tons Percent

Total

1995 152,033 40 73,725 19 154,570 41

1996 131,344 36 73,504 20 156,040 43

1997 122,685 33 65,049 17 187,502 50

1998 125,021 33 64,199 17 190,727 50

1999 134,868 34 74,174 19 186,426 47

2000 129,498 32 72,197 18 200,558 50

2001 135,149 33 71,808 18 202,858 49

2002 131,390 33 74,264 19 191,922 48

2003 131,370 33 68,396 17 204,320 51

2004 136,362 34 67,274 17 193,407 49

2005 140,135 34 57,312 14 220,151 53

2006 158,277 36 59,786 13 226,902 51

2007 153,070 33 65,750 14 245,278 53

Export

1995 50,616 38 67,631 51 14,719 11

1996 46,836 37 66,921 53 11,486 9

1997 43,696 40 58,426 54 6,739 6

1998 41,700 39 57,509 54 7,369 7

1999 50,657 41 67,949 55 4,892 4

2000 46,040 38 67,556 55 9,020 7

2001 48,547 40 67,189 55 6,070 5

2002 45,935 39 68,505 59 2,660 2

2003 47,117 40 62,776 54 7,361 6

2004 49,897 41 61,729 51 9,626 8

2005 56,570 49 52,625 46 5,840 5

2006 64,389 51 55,919 44 6,662 5

2007 64,208 46 61,613 44 14,780 11

Domestic

1995 101,417 41 6,094 3 139,851 57

1996 84,509 36 6,583 3 144,555 61

1997 78,989 30 6,624 2 180,763 68

1998 83,322 30 6,690 2 183,357 67

1999 84,211 31 6,225 2 181,534 67

2000 83,458 30 4,641 2 191,537 68

2001 86,602 30 4,619 2 196,789 68

2002 85,454 30 5,759 2 189,262 67

2003 84,253 29 5,620 2 196,959 69

2004 86,465 31 5,544 2 183,781 67

2005 83,565 28 4,686 2 214,310 71

2006 93,889 30 3,867 1 220,240 69

2007 88,862 27 4,137 1 230,499 71
9

As with tonnages, the modal share percentages are different for domestic than for export movements. 

The principal mode for the domestic market is truck and, in recent years, rail has moved the highest 

percentage of grain exports. Barge had been the principal mode of transport for export grain until 2005. 

Barge lost some shares in the export market beginning in the fall of 2004, when the decrease in the barge 

fl eet size began to affect barge availability as the demand for non-grain commodities increased. Barge 

rates continued their increase the following year when Hurricane Katrina disrupted barge logistics in the 

third quarter of 2005. Table 3 shows a summary of modal shares for each of the three major grains for 

2007 compared with the average for the 5 years from 2003-2007. 

The next section examines modal characteristics for corn, wheat, and soybeans. Data on sorghum and 

barley can be found in Appendix D.

Table 3: Modal Share Summary: 2007 and 5-year average, percent

Mode/

Year

Corn Wheat Soybeans All grains

Exports Domestic All corn Exports Domestic All 

wheat Exports Domestic All soybeans Exports Domestic All grains

Rail

2007 35 26 28 66 65 66 41 14 24 46 27 33

5-yr avg 36 29 30 67 55 61 39 14 24 45 29 34

Barge

2007 55 1 13 28 1 16 46 2 18 44 1 14

5-yr avg 59 1 14 30 1 15 52 3 21 48 2 15

Truck

2007 10 73 59 6 34 19 12 84 57 11 71 53

5-yr avg 5 70 56 4 43 24 9 83 56 7 69 51
10

During 1995 to 2007, corn accounted for 59 percent of all grain movements. It dominated the bulk 

transportation market because of its large production volumes. Corn usually has the largest harvested 

acreage of any crop, although soybean acreage has risen in the last several years and sometimes 

surpasses the number of corn acres. However, the high yield-per-acre of corn makes it a driver in the 

grain transportation market. Corn yields can be more than three times those of soybeans or wheat.

Corn is transported from production areas to distant markets in two patterns: one for domestic use and 

the other for export. Table 4 shows total corn, export, and domestic movements during 1995 to 2007. 

Trucks supply most of the transportation for the domestic market, and barges for the export market. The 

corn grower can truck to more buyers, allowing more choices in fi nding the highest bidder because of 

the fl exibility of trucking. On the export side, the overall consideration is moving large volumes of grain 

long distances while keeping commodity prices competitive. Trucking corn from St. Louis to New Orleans 

would not make economic sense. Barge or rail could move the corn more effi ciently, and usually barge 

offers the more competitive rate from the Midwest to coastal areas for export. From 1995 to 2007, trucks 

transported, on average, about 67 percent of the corn used by the domestic market. During the same 

period, barges transported 63 percent of the corn exports. Rail handled about 32 percent of the export 

market and 31 percent of the domestic market. Barges continue to be the main mode of transportation 

for corn moving to port regions for export. From 1995 to 2007, the modal share trend has been relatively 

stable for exported corn. Rail share went from 33 to 35 percent, while barge share went from 58 to 55 

percent during that time period. 

Corn Modal Shares
11

Table 4: Tonnages and modal shares for U.S. corn, 1995–2007 

Year & 

type of 

movement

Mode of transport

Rail Barge Truck

1,000 tons Percent 1,000 tons Percent 1,000 tons Percent

Total

1995 79,333 37 40,778 19 97,407 45

1996 66,015 34 39,162 20 89,626 46

1997 61,582 30 31,343 15 114,931 55

1998 63,470 30 33,995 16 112,511 54

1999 71,807 32 40,620 18 111,447 50

2000 68,984 30 37,831 16 122,531 53

2001 73,633 31 38,864 16 125,340 53

2002 72,615 31 41,598 18 119,713 51

2003 71,443 30 36,488 15 127,916 54

2004 77,377 32 37,302 15 126,588 52

2005 77,908 30 31,739 12 150,519 58

2006 91,552 32 34,587 12 159,086 56

2007 81,170 28 37,407 13 171,999 59

Export

1995 21,665 33 38,098 58 5,438 8

1996 16,179 28 35,883 63 5,133 9

1997 15,061 33 27,747 60 3,186 7

1998 12,240 27 30,592 68 2,033 5

1999 18,307 32 37,533 65 1,980 3

2000 15,213 29 35,150 66 2,594 5

2001 15,822 30 35,904 68 1,306 2

2002 14,327 27 38,125 73 0 0

2003 14,371 30 32,872 69 364 1

2004 17,422 33 33,974 64 1,978 4

2005 20,251 40 28,778 57 1,600 3

2006 28,145 44 31,941 50 3,342 5

2007 22,352 35 34,689 55 6,429 10

Domestic

1995 57,668 38 2,680 2 91,969 60

1996 49,837 36 3,279 2 84,493 61

1997 46,521 29 3,596 2 111,744 69

1998 51,230 31 3,403 2 110,478 67

1999 53,501 32 3,087 2 109,467 66

2000 53,771 30 2,681 2 119,936 68

2001 57,811 31 2,960 2 124,034 67

2002 58,288 32 3,473 2 119,835 66

2003 57,072 30 3,616 2 127,552 68

2004 59,955 32 3,328 2 124,611 66

2005 57,657 28 2,961 1 148,918 71

2006 63,407 29 2,646 1 155,744 70

2007 58,818 26 2,718 1 165,570 73
12

Figures 6 and 7 illustrate the relative importance of trucks to domestic movements of corn and the relative 

importance of barges to export corn movements.

Figure 6: U.S. corn domestic shipments by mode, 1995–2007

Figure 7: U.S. corn export shipments by mode, 1995–2007

0

20

40

60

80

100

120

140

160

180

200

220

240

1995 1996 1997 1998 1999 2000 2001 2002 2003 2004 2005 2006 2007

Million Tons

Year

Truck Barge Rail

0

20

40

60

80

100

120

140

160

180

200

220

240

1995 1996 1997 1998 1999 2000 2001 2002 2003 2004 2005 2006 2007

Million Tons

Year

Truck Barge Rail
13

Corn Supply and Demand

Supply and demand patterns in the U.S. corn market have shifted dramatically since 1990. Domestic 

and export shares have decreased and the share used by industry has grown substantially. Feed use has 

decreased from 59 percent of production in the 1990/91 marketing year to 47 percent in 2007/08; exports 

decreased from 22 to 19 percent. During the same period, industrial use increased from 18 percent to 34 

percent (Table 5). Most of the change occurred after the rapid expansion of the ethanol sector. 

Domestic demand for feed corn has grown by only 29 percent between the 1990/91 and 2007/08 

marketing years (Table 6). But demand for corn for food, seed, and industrial products, including ethanol, 

has surged by 206 percent. About a third of the corn used to make ethanol ends up as distillers grains. 

The use of distillers grains as animal feed is increasing domestically and in overseas markets such as 

China, Mexico, and the Middle East. Corn exports peaked in 2007/08 at a record 2.4 billion bushels—41 

percent higher than in 1990/91. 

Table 5: Corn usage by sector, percentage

Feed Exports Industrial

1990/91 59 22 18

2007/08 47 19 34

Table 6: U.S. corn supply and use for various marketing years, million bushels

Marketing 

Yeara

Supply Disappearance

Beginning 

stocks Production Imports Total 

Food, 

seed, and 

alcohol

Feed and 

residual Exports Total

1990/91 1,344 7,934 3 9,282 1,425 4,609 1,727 7,761 

2000/01 1,718 9,915 7 11,639 1,957 5,842 1,941 9,740 

2001/02 1,899 9,503 10 11,412 2,046 5,864 1,905 9,815 

2002/03 1,596 8,967 14 10,578 2,340 5,563 1,588 9,491 

2003/04 1,087 10,087 14 11,188 2,537 5,793 1,900 10,230 

2004/05 958 11,806 11 12,775 2,687 6,155 1,818 10,661 

2005/06 2,114 11,112 9 13,235 2,982 6,152 2,134 11,268 

2006/07 1,967 10,531 12 12,510 3,490 5,591 2,125 11,207 

2007/08 1,304 13,038 20 14,362 4,363 5,938 2,436 12,737 

2008/09 1,624 12,092 14 13,729 5,025 5,182 1,849 12,056 

2009/10b 1,673 13,110 8 14,792 5,938 5,159 1,987 13,084 

a Marketing Year: September 1-August 31

b Estimate, WASDE, December 10, 2010
14

Corn Transportation Characteristics

In 2007, more than 60 percent of U.S. corn was harvested in fi ve States: Iowa, Illinois, Nebraska, 

Minnesota, and Indiana. Demand for corn, however, was diverse, creating areas of defi cit throughout the 

livestock feeding areas of the West, Texas, the Southeast, and Northeast. Corn is also shipped to export 

port regions in the Gulf, the Pacifi c Northwest, the Atlantic Coast, and the Great Lakes. The map in Figure 

8 demonstrates how long distance transportation is needed to close the geographic gap between the 

surplus and defi cit regions.

Figure 8: Corn surplus/defi cit map with the transportation system 

Source: Census of Agriculture, 2007 and Economic Research Service, USDA. Surplus-defi cit estimate is based on 

county-level production, U.S. feed use, and county-level animal inventories (summed based on Grain Consuming 

Animal Unit factors). U.S. Waterborne Exports and Imports from the Port Import Export Reporting Service (PIERS).
15

Because of the projected trend in supply and demand, long-term transportation demand for corn exports 

can be expected to grow at a stable rate. Domestic corn transportation patterns continue to be dominated 

by the dynamics of corn used for ethanol and distillers grain because the growth of the ethanol industry 

in the Corn Belt introduced additional transportation needs. More than 90 percent of ethanol production 

capacity is located within a 50-mile radius of the corn producing areas, so trucks have been the primary 

mode of transportation for inbound corn. However, the newer and larger bio-refi neries are able to receive 

corn shipments by rail. 
16

From 1995 to 2007, wheat accounted for 16 percent of all grain movements. The major wheat production 

region is in the Plains States, where rail is the dominant mode of transportation (Table 7). 

Wheat Modal Shares

Table 7: Tonnages and modal shares for U.S. wheat, 1995-2007

Year & 

type of 

movement

Mode of transport

Rail Barge Truck

1,000 tons Percent 1,000 tons Percent 1,000 tons Percent

Total

1995 42,692 66 12,153 19 9,738 15

1996 37,662 55 12,239 18 18,863 27

1997 34,397 54 11,534 18 18,168 28

1998 37,119 54 10,756 16 20,984 30

1999 37,568 54 12,038 17 19,616 28

2000 35,380 51 12,391 18 22,137 32

2001 33,269 52 11,534 18 19,668 31

2002 32,702 56 9,876 17 16,081 27

2003 34,181 53 10,180 16 20,428 32

2004 37,302 56 11,937 18 17,625 26

2005 39,287 63 8,312 13 14,759 24

2006 38,596 67 8,068 14 11,302 19

2007 43,953 66 10,515 16 12,484 19

Export

1995 20,470 58 11,221 32 3,824 11

1996 19,985 56 11,449 32 3,986 11

1997 16,796 58 10,884 38 1,281 4

1998 18,824 63 10,083 34 1,162 4

1999 19,556 59 11,558 35 2,016 6

2000 17,934 56 11,975 38 1,871 6

2001 16,549 56 11,099 38 1,762 6

2002 16,988 62 9,367 34 1,225 4

2003 17,983 61 9,726 33 1,681 6

2004 21,045 61 11,370 33 2,294 7

2005 22,452 74 7,938 26 0 0

2006 18,922 71 7,868 29 0 0

2007 24,653 66 10,229 28 2,197 6

Domestic

1995 22,222 76 932 3 5,914 20

1996 17,677 53 790 2 14,878 45

1997 17,602 50 650 2 16,887 48

1998 18,295 47 672 2 19,822 51

1999 18,012 50 480 1 17,600 49

2000 17,446 46 416 1 20,267 53

2001 16,720 48 435 1 17,906 51

2002 15,714 51 509 2 14,856 48

2003 16,198 46 454 1 18,747 53

2004 16,256 51 566 2 15,330 48

2005 16,835 53 375 1 14,759 46

2006 19,674 63 200 1 11,302 36

2007 19,300 65 286 1 10,286 34
17

Wheat is moved long distances to export ports and domestic markets. Consequently, trucks are not 

an economical mode for moving wheat. Most classes of wheat are produced in areas where barge 

transportation is not accessible, so rail is the leading provider of transportation for both the domestic and 

export market (Figure 9 and Figure 10).

0

10

20

30

40

50

1995 1996 1997 1998 1999 2000 2001 2002 2003 2004 2005 2006 2007

Million Tons

Year

Rail Barge Truck

Figure 9: U.S. wheat domestic shipments by mode, 1995–2007

Figure 10: U.S. wheat export shipments by mode, 1995-2007

0

10

20

30

40

1995 1996 1997 1998 1999 2000 2001 2002 2003 2004 2005 2006 2007

Million Tons

Year

Rail Barge Truck
18

Wheat Supply and Demand

Wheat production in the United States has declined since 1990/91 because of slow growth in global 

demand for U.S. wheat, and because corn and soybeans provide a higher return on investment. In the 

2007/08 marketing year, however, U.S. wheat exports surged unexpectedly due to a weather-related 

shortfall in production by other major exporters (Table 8). This reduced available world wheat supplies 

and resulted in importing countries buying more U.S. wheat than they had done in the recent past. 

Various types of wheat are grown in highly concentrated production areas of the United States and the 

grain must be dispersed for use throughout the country. Seasonality of the types of wheat can affect 

its transportation because transportation needs are typically at their highest levels during harvest. The 

harvest seasons of the two major types of wheat—winter and spring—grown in the United States take 

place in May through June and August through September, respectively. 

Table 8: U.S. wheat supply and use for various marketing years, million bushels

Marketing 

Yeara

Supply Disappearance

Beginning 

stocks Production Imports Total Food

Feed, 

seed, and 

residual

Exports Total

1990/91 536 2,730 36 3,302 790 575 1,069 2,434 

2000/01 950 2,228 90 3,268 950 379 1,062 2,391 

2001/02 876 1,947 26 2,849 926 265 962 2,153 

2002/03 777 1,606 77 2,460 919 200 850 1,969 

2003/04 491 2,344 63 2,899 912 283 1,158 2,353 

2004/05 546 2,157 71 2,774 910 259 1,066 2,235 

2005/06 540 2,103 81 2,725 917 234 1,003 2,154 

2006/07 571 1,808 122 2,501 938 199 908 2,045 

2007/08 456 2,051 113 2,620 947 103 1,264 2,314 

2008/09 306 2,499 127 2,932 927 333 1,015 2,275 

2009/10b 657 2,218 119 2,994 917 219 881 2,147 

a Marketing Year: June 1-May 31

b Estimate, WASDE, December 10, 2010
19

Wheat Transportation Characteristics

In 2007, almost 83 percent of U.S. wheat was grown in 10 States: North Dakota, Kansas, Montana, South 

Dakota, Texas, Washington, Oklahoma, Colorado, Nebraska, and Idaho.3 However, the demand for wheat 

is dispersed throughout the population centers of the United States. In addition, almost 45 percent of 

the U.S. wheat crop is exported through the major U.S. port regions to overseas destinations. The map 

in Figure 11 demonstrates the relationship between wheat production and consumption areas and the 

importance of the transportation system.

3 USDA-NASS

Figure 11: Wheat surplus/defi cit map with the transportation system 

Source: Census of Agriculture, 2007 and Economic Research Service, USDA. Surplus-defi cit estimate is based on 

county-level production and consumption (based on population and per capita fl our consumption). U.S. Waterborne 

Exports and Imports from the Port Import Export Reporting Service (PIERS).
20

From 1995 to 2007, soybeans accounted for 20 percent of all grain movements. Their transportation 

pattern resembles that of corn; barges provide most of the transportation for export and trucks serve 

most of the domestic markets. From 2005 to 2007, the rail share of export soybeans has been above 

40 percent. Due to the rising demand for U.S. soybeans in Asia, soybean exports have increased out of 

the Pacifi c Northwest, and the rail share of export soybeans has increased as a result. Table 9 shows the 

tonnages and modal share for total, export, and domestic soybean movements. With an average domestic 

modal share for truck of 79 percent, the domestic soybean market relies upon trucks more than corn 

does, the latter having a truck modal share of 67 percent. Soybeans used in the domestic market are 

more likely to be trucked to a crushing facility, so more trucked soybeans appear in the domestic market.

Figures 12 and 13 show the modal share of domestic and export soybean movements. 

Soybean Modal Shares
21

Year & 

type of 

movement

Mode of transport

Rail Barge Truck

1,000 tons Percent 1,000 tons Percent 1,000 tons Percent

Total

1995 17,067 24 18,399 26 35,026 50

1996 18,863 27 20,337 29 30,068 43

1997 16,976 23 20,374 28 36,198 49

1998 16,476 21 18,000 23 42,372 55

1999 16,685 22 19,875 26 40,941 53

2000 17,257 22 20,174 26 41,225 52

2001 20,662 24 19,872 23 44,813 53

2002 19,120 22 21,399 25 44,848 53

2003 20,216 24 20,167 24 44,409 52

2004 16,346 22 17,053 23 39,337 54

2005 17,655 22 16,332 21 45,501 57

2006 21,858 25 16,221 19 49,564 57

2007 21,705 24 16,327 18 51,373 57

Export

1995 5,572 23 16,308 66 2,880 12

1996 7,895 31 17,922 69 23 0

1997 7,912 30 18,091 69 337 1

1998 7,299 29 15,410 61 2,741 11

1999 8,189 32 17,240 68 80 0

2000 8,591 29 18,665 63 2,442 8

2001 11,711 37 18,689 59 1,262 4

2002 10,602 35 19,642 64 263 1

2003 12,479 37 18,632 55 2,878 8

2004 9,322 34 15,412 56 2,977 11

2005 11,273 40 15,030 53 1,815 6

2006 14,169 46 15,240 49 1,654 5

2007 13,584 41 15,242 46 3,998 12

Domestic

1995 11,495 25 2,091 5 32,145 70

1996 10,968 25 2,416 6 30,045 69

1997 9,064 19 2,283 5 35,861 76

1998 9,177 18 2,590 5 39,631 77

1999 8,496 16 2,636 5 40,861 79

2000 8,666 18 1,510 3 38,783 79

2001 8,950 17 1,183 2 43,552 81

2002 8,518 16 1,758 3 44,586 81

2003 7,737 15 1,535 3 41,531 82

2004 7,024 16 1,641 4 36,361 81

2005 6,382 12 1,302 3 43,686 85

2006 7,688 14 982 2 47,910 85

2007 8,121 14 1,086 2 47,375 84

Table 9: Tonnages and modal shares for U.S. soybeans, 1995-2007
22

Figure 13: U.S. soybean export shipments by mode, 1995-2007 

Figure 12: U.S. soybean domestic shipments by mode, 1995-2007 

0

10

20

30

40

50

60

1995 1996 1997 1998 1999 2000 2001 2002 2003 2004 2005 2006 2007

Million Tons

Year

Rail Barge Truck

0

10

20

30

40

50

60

1995 1996 1997 1998 1999 2000 2001 2002 2003 2004 2005 2006 2007

Million Tons

Year

Rail Barge Truck
23

Soybean Supply and Demand

The 65 percent growth in the global economy since 1990 has contributed to the rise in world demand for 

meat, milk, and eggs.4 This demand has translated into demand for U.S. soybeans and soy meal used 

as a high protein livestock feed. Between 1990 and 2008, domestic demand for soybeans grew by 52 

percent and soybean exports increased by 108 percent (Table 10). USDA estimates that U.S. soybean 

exports will reach a record level in 2009/10, and could continue to increase during the decade to fulfi ll the 

growing demand for soybeans in Asia. A continuing demand for soybean exports will require effi cient and 

reliable rail and barge transportation.

4 World Perspectives, Inc.

Table 10: U.S. soybean supply and use for various marketing years, million bushels

Marketing 

Yeara

Supply Disappearance

Beginning 

stocks Production Total Crush Exports Seed and residual Total

1990/91 239 1,926 2,165 1,187 557 96 1,840 

2000/01 290 2,758 3,048 1,640 996 168 2,804 

2001/02 248 2,891 3,138 1,700 1,064 169 2,933 

2002/03 208 2,756 2,964 1,615 1,044 131 2,791 

2003/04 178 2,454 2,632 1,530 887 109 2,525 

2004/05 112 3,124 3,236 1,696 1,097 193 2,986 

2005/06 256 3,063 3,319 1,739 940 194 2,873 

2006/07 449 3,197 3,646 1,808 1,116 157 3,081 

2007/08 574 2,677 3,251 1,801 1,161 93 3,055 

2008/09 205 2,967 3,185 1,662 1,279 106 3,047 

2009/10b 138 3,359 3,512 1,752 1,501 108 3,361 

a Marketing Year: September 1-August 31

b Estimate, WASDE, December 10, 2010
24

Soybean Transportation Characteristics 

As with corn, the top soybean producing States are Iowa, Illinois, Minnesota, Indiana, Ohio, and Nebraska. 

However, demand for soybean products in feed rations is distributed around the U.S. markets and port 

regions for export (Figure 14).

Figure 14: Soybean surplus/defi cit map with the transportation system 

Source: Census of Agriculture, 2007 and Economic Research Service, USDA. Surplus-defi cit estimate is based on 

county-level production, U.S. soybean meal use (soybean equivalent), and county-level animal inventories (summed 

based on High Protein Animal Unit factors). U.S. Waterborne Exports and Imports from the Port Import Export 

Reporting Service (PIERS).
25

From 1983 to 2009, the prominent port area for handling grain exports was the Mississippi River-Gulf of 

Mexico Ports.5

These ports, commonly referred to as New Orleans, comprise four major deep-draft ports. The Louisiana 

ports of Port of South Louisiana, New Orleans, Baton Rouge, and Port of Plaquemines, collectively have 

access to six Class I railroads, three interstate highways, and waterway access to the Midwest. These 

factors have given the area a signifi cant advantage for shipping goods from the U.S. to foreign countries.

Figure 15 shows that the Mississippi Gulf handled from 44 to 62 percent of all grain exports. The Pacifi c 

Northwest (PNW) is the second largest grain port area, handling 15 to 28 percent. The Texas Gulf of 

Mexico ports handled 9 to 18 percent and the Great Lakes ports handled 1 to 7 percent. Other ports 

handled grain, but far less. A complete list of ports and port areas can be found in Appendix C. 

5 Data for port share of exports calculations were derived from grain export inspections records collected by USDA’s Grain 

Inspection, Packers and Stockyards Administration, Federal Grain Inspection Service (FGIS). Most grain exported from the United 

States requires FGIS inspection. Mandatory inspection requirements do not apply to grain which is not sold or described by grade. 

These requirements also are waived for grain exporters shipping less than 15,000 metric tons of grain abroad annually, for grain 

exported by train or truck to Canada or Mexico, for grain sold as “seed,” and for grain transshipped through the United States in a 

bonded identity-preserved fashion. Data for 1978 to 1982 was not available.

Exports by Port Area

Figure 15: Port share of grain exports, 1983-2009 

0%

10%

20%

30%

40%

50%

60%

70%

198319841985198619871988198919901991199219931994199519961997199819992000200120022003200420052006200720082009

Port %

Year

Mississippi River Gulf PNW Texas Gulf Great Lakes
26

Transportation implications of the annual port share shows that when the Mississippi River share of grain 

exports increases so does the barge share and when the Mississippi River share declines, so does the 

barge share. Likewise, when PNW or Texas Gulf exports increase, rail’s share of exports increases. PNW 

can receive grain by barge on the Columbia-Snake River System, but most grain exported out of PNW is 

delivered to port by rail. 

Changes in a port’s share are also infl uenced by international transportation rates. Ocean rates to Asia 

from PNW are generally lower than ocean rates to Asia from the Mississippi Gulf. The ocean freight 

difference between PNW and Mississippi Gulf impacts the relative changes between the ports’ share 

of exports.

Recent Trends. Beginning in 2002, the share from the Mississippi Gulf of total grain exports began a 

steady decline as the port share from PNW increased. Several factors have contributed to the shift. Since 

the beginning of 2002, fl uctuations in production, trade, and stocks of agricultural commodities have been 

unusually large.6 From 2002 to 2008, prices rose more than 250 percent for corn, nearly 300 percent 

for soybeans, and 330 percent for wheat. With increased demand from Asia, higher commodity prices, 

and more attractive ocean shipping rates, U.S. grain exporters began to shift some trade to PNW ports. 

Typically, PNW ports offer lower oceans rates to Asia than the Mississippi Gulf Ports. However, overland 

costs from the major U.S. grain production regions are higher to PNW than to the Mississippi Gulf ports 

because shipping grain by barge to the Gulf is less costly than shipping via rail to PNW ports.

6 USDA Agricultural Projections to 2019: Offi ce of the Chief Economist, World Agricultural Outlook Board, U.S. Department of 

Agriculture, February 2010.
27

Corn Exports by Port Area

From 1983 to 2009, the Mississippi Gulf Ports consistently handled over half of all corn exports, ranging 

from 55 to 81 percent. PNW handled 9 to 26 percent of all corn exports. Interior locations7 handled 2 to 

14 percent (Figure 16).

Corn Recent Trends. As did the trends of total grain exports, the share of total corn exports from the 

Mississippi Gulf began to drop in 2002, as the share of exports from PNW increased. In addition to the 

growing demand in Asia, the corn market underwent signifi cant changes with a rapid expansion of ethanol 

production in 2005. A growing portion of the co-product of ethanol production, distillers grain, is now 

exported as animal feed, which may help mitigate some of the reduced corn exports not shipped through 

the Mississippi Gulf in recent years. In 2009, Mississippi Gulf customs district was the leading port for 

exporting distillers grain, followed by the California ports of Los Angeles and San Francisco, and overland 

routes to Mexico in Texas, Arizona, and Southern California.

7 Interior locations can be anywhere in the country where the grain is inspected, and then transported to an export facility. 

Interior inspections are useful when certain qualities of the grain need to be verifi ed by the buyer.

Figure 16: Port share of corn exports, 1983-2009 

0%

10%

20%

30%

40%

50%

60%

70%

80%

90%

198319841985198619871988198919901991199219931994199519961997199819992000200120022003200420052006200720082009

Port %

Year

Mississippi River Gulf PNW Interior Locations
28

Wheat Exports by Port Area

Unlike corn and soybeans, the current predominate port area for handling export wheat is PNW (Figure 

17). Before 1989, the Texas Gulf shipped the most export wheat. Many factors have contributed to the 

shift in port shares of wheat. Prior to the 1990’s, the Texas Gulf was the leading wheat port when Europe 

was a signifi cant market for U.S. grains. Since then, Europe has declined in importance as other markets, 

such as Asia, have become larger. Also, unlike corn and soybeans, different classes of wheat infl uence 

where the wheat is moved to export. The fi ve major classes of U.S. wheat are hard red winter, hard red 

spring, soft red winter, white, and durum. Each class has a somewhat different end use and production 

tends to be region-specifi c.8 Hard red winter (HRW) wheat accounts for about 40 percent of total 

production and is grown primarily in the Great Plains (Texas north through Montana). Hard red spring 

(HRS) wheat accounts for about 25 percent of production and is grown primarily in the Northern Plains 

(North Dakota, Montana, Minnesota, and South Dakota). 

Wheat Recent Trends. In 1999, PNW and Texas Gulf had nearly the same port share of export wheat: 

34 percent and 33 percent, respectively. Since 1999, however, PNW has gained more port share than the 

Texas Gulf. The port share from the Mississippi Gulf has decreased while the export share from the Great 

Lakes has fl uctuated in the single digit percent range. 

In the 1990s and 2000s, world wheat demand increased as a result of rising populations and incomes. 

The growing market of smaller scale purchases by a larger number of importing countries—in Southeast 

Asia, North Africa, and the Middle East—have become more signifi cant in the wheat market than the very 

large purchases in the past by the former Soviet Union and China.9

8 http://www.ers.usda.gov/briefi ng/wheat/background.htm

9 http://www.ers.usda.gov/briefi ng/wheat/background.htm

Figure 17: Port share of corn exports, 1983-2009 

0%

10%

20%

30%

40%

50%

60%

198319841985198619871988198919901991199219931994199519961997199819992000200120022003200420052006200720082009

Port %

Year

Mississippi River Gulf PNW Texas Gulf Great Lakes
29

Soybean Exports by Port Area

From 1983 to 2009, there has been a general decline in the Mississippi River’s port share of soybean 

exports. During the same time, PNW and the interior’s share of port exports have been increasing (Figure 

18). PNW has grown in importance as a port for export soybeans due to many factors. The growth in 

Asian demand for U.S. soybeans and favorable ocean freight rates can give PNW an advantage over other 

U.S. ports. The growth in interior shipments refl ects the growth in containerized export grain. This would 

cause a decrease in the barge share of export soybeans, and an increase in rail’s share.

Soybean Recent Trends. Since 1991, the Mississippi Gulf lost a signifi cant amount of port share for 

soybeans—dropping from 80 percent to 55 percent—while the port share of PNW increased from 5 percent 

to 24 percent. Transportation factors favor PNW, as China and Southeast Asia have been among the 

strongest import markets for soybeans and should continue to be growth markets. Also, improvements in 

soybean genetics allowed for a geographic expansion of the major soybean producing areas that favored 

PNW because some of the production area is now closer to that port.

Figure 18: Port share of soybean exports, 1983-2009 

0%

10%

20%

30%

40%

50%

60%

70%

80%

90%

198319841985198619871988198919901991199219931994199519961997199819992000200120022003200420052006200720082009

Port %

Year

Mississippi River Gulf PNW Interior Locations
30

The most signifi cant trends during 1978–2007 were the upward growth in tonnages of all grains moved 

and an increased truck share in moving that grain. Total grain movements increased 92 percent in 

those 30 years. These trends were driven by increases in production and domestic off-farm grain use, 

particularly for corn. 

From 1978 to 2007, the trucking sector experienced the largest growth among modes of grain 

movements. Truck tonnages increased from 74 million to 245 million tons—growing at a compound 

annual growth rate (CAGR) of 4.1 percent. During this period, rail movements increased from 117 million 

to 153 million tons (0.9 percent CAGR), and barge movements from 51 million to 66 million tons (0.9 

percent CAGR).

In terms of percent of total movements, truck became the dominant mode in 1993 and since then its 

share has generally been increasing over rail and barge. Truck share displayed a general upward trend, 

from 31 percent in 1978 to 48 percent, in 2007. The share of rail movements decreased during that 

period from 48 to 33 percent, while barge decreased from 21 to 14 percent.

Transportation implications of the annual port share show that when the share of Mississippi River 

exports increases, so does the barge share of grain exports. When Mississippi River’s share declines, so 

does barge’s. Also, when PNW or Texas Gulf exports increase, rail share of exports increase. PNW can 

receive grain by barge on the Columbia-Snake River System; however, most grain exported out of PNW is 

delivered to port by rail. 

As the study indicates, modal share of the fi nal movement of grain is highly dependent upon the type of 

grain being transported and shipment origination and destination markets. Fundamental economic theory 

shows that prices in areas of scarcity are high as compared to areas of abundance. The price of corn is 

greater in Louisiana than the Midwest. That price difference, and the possibility to profi t by moving the 

commodity by lowest transportation cost, provides an incentive to market grain. The movement of grain 

to export facilities is best handled with high-volume long-haul modes of transportation, such as barge or 

rail. Therefore, high levels of grain exports increase demand for rail and barge transportation. Increased 

domestic off-farm feed use and increased domestic demand for processed grain products drive up demand 

for truck transportation. Adequate rail, barge, and truck transportation are all essential to a grain 

transportation infrastructure that supports the domestic and export market expansion of U.S. grain.

Conclusion
31

Agricultural Marketing Service, Livestock and Seed Programs, Livestock and Grain Market News, USDA. 

Grain and Feed Summary and Statistics. Washington DC, various issues.

Association of American Railroads, Commodity Freight Statistics. Washington, DC: AAR, 1996–07.

Bureau of Transportation Statistics. United States Department of Transportation, Atlas Databases 2002, 

CD-ROM: BTS, 2002.

Economic Research Service, USDA. Briefi ng Room, Corn. http://www.ers.usda.gov/briefi ng/corn.

Economic Research Service, USDA. Briefi ng Room, Soybeans and Oil Crops. http://www.ers.usda.gov/

briefi ng/SoybeansOilCrops.

Economic Research Service, USDA. Briefi ng Room, Wheat. http://www.ers.usda.gov/briefi ng/Wheat.

Economic Research Service, USDA. Feed Outlook. http://www.ers.usda.gov/publications/so/view.

asp?f=fi eld/fds-bb/. Washington DC, various issues.

Economic Research Service, USDA. Key Topics, Crops, Sorghum. http://www.ers.usda.gov/topics/view.

asp?T=101220.

Economic Research Service, USDA. Oil Crops Outlook.

http://ers.usda.gov/publications/so/view.asp?f=fi eld/ocs-bb/. Washington, DC, various issues.

Economic Research Service, USDA. Wheat Outlook. http://www.ers.usda.gov/publications/so/view.

asp?f=fi eld/whs-bb/. Washington, DC, various issues.

National Agricultural Statistics Service, USDA. http://www.usda.gov/nass/. 

Renewable Fuels Association. Washington, DC.

Surface Transportation Board. Master Carload Waybill Sample. 1996–2007.

Texas Transportation Institute, Center for Ports and Waterways. A Modal Comparison of Freight 

Transportation Effects on the General Public.

U.S. Army Corps of Engineers. Waterborne Commerce of the United States. Institute for Water 

Resources, Alexandria, VA: 1996–2007.

Bibliography
32

Modal shares are calculated for all grains and each grain type, based on the estimated modal tonnages. 

These modal shares are determined for total, export, and domestic movements.

Total Tonnages. The approach used to estimate modal tonnages and shares requires that total tonnages 

of grain transported to market be determined. It is also neces sary to determine the portions of total 

tonnages transported to domestic and export markets. Total tonnages are defi ned as total disappearance 

minus grain that was grown and used on-farm. Total disappearance for this study is calculated using the 

ERS Wheat Outlook, Feed Outlook, and Oil Crop Outlook reports. These reports include marketing year 

supply and disappearance tables that list domestic use and exports. The Oil Crop Outlook lists these 

numbers by marketing year. The other two reports break the numbers down on a quarterly basis. To get 

disappearance numbers for calendar years 1995 through 2007, monthly totals are calculated from the 

marketing year data and added together into respective calendar year totals. 

Total Export. Total exports are calculated using export numbers reported in the ERS Outlook reports. 

Total Domestic. Total domestic tonnages are estimated by subtracting total export tonnages from 

total disappearance.

Grown and Used-on-Farm Totals. Grown and used-on-farm data are provided by ERS. These data 

are reported in percentages by year and commodity. Production numbers for each commodity are 

multiplied by the grown and used-on-farm percentages. Those numbers are then subtracted from total 

disappearance to get total transported grain tonnages. Grain grown and used on-farm must be deducted 

from total disappearance because it generates no commercial transporta tion demand.

Rail Total. Rail movements for 1996 to 2007 came from the STB Master Carload Waybill Sample. STB’s 

Waybill Sample is a stratifi ed sample of carload waybills for terminated shipments by railroad carriers. 

The STB collects operating statistics on U.S. railroads, which can be used to estimate rail traffi c volumes 

and railroad characteristics. Total tonnages are calculated using the billed weight in tons from the Waybill 

Sample and multiplying it by an expansion factor to estimate the tonnages for all grain movements by 

all railroads. Movements that originated and terminated in the same fi ve-digit, Federal Information 

Processing Standards (FIPS) region are assumed to be short hauls, which would be double-counted and, 

thus, were deleted. 

Some grain is moved by a combination of rail and barge. Since this represents a relatively small amount 

of grain, these movements are not included in the rail calculations. Instead, they are counted in the 

barge movements—the fi nal mode used to transport the grain. There are other instances in which grain 

shipments are rebilled from one railroad to another at terminal markets. Such a movement would be 

considered a double-count of grain movements. An attempt is made to minimize the rebilled movements. 

Again, as with the rail-to-barge movements, these types of shipments represent a small portion of total 

rail shipments.

Rail Export. Export regions are defi ned by fi ve-digit FIPS codes and are listed in Appendix B. The 

regions chosen are based on methodology from the 1998 modal share report as those regions with 

ports in the Pacifi c Northwest, Atlantic Coast, and Gulf of Mexico. Rail exports to the Great Lakes are 

determined from grain delivery information at Duluth-Superior, MN, and Toledo, OH. Total tonnages 

exported are then calculated using the designated export regions. Movements that originated and 

terminated in the same fi ve-digit FIPS region are assumed to be short hauls, which would be doublecounted and, thus, were deleted. 

Appendix A: Modal Share Methodology
33

Rail Domestic. Domestic rail tonnages are estimated by subtracting export grain tonnages moved by rail 

from total grain tonnages moved by rail.

Barge Total. Barge movement data for 1996–2007, which are collected and compiled by the U.S. Army 

Corps of Engineers, are obtained from Waterborne Commerce of the United States. The categories 

used to calculate modal shares for barge are river shipping range (origin) and river receiving range 

(destination). Total movements are determined by summing the total of all receiving ranges. As 

explained in the Rail Total section above, when barge and rail are used in combination to ship grain, with 

barge being the fi nal mode in the transportation route, only the barge movement is included. 

Barge Export. The following river receiving ranges are used to fi nd barge export movements: Atlantic, 

Pacifi c, Central Gulf, East Gulf, and West Gulf. Any movement that is received into a port in the defi ned 

regions is determined to be an export movement. The receiving ranges are based on the 1998 report’s 

methodology. For that report, export barge modal shares were calculated using barge export tonnages 

based on internal grain and oilseed receipts reported on the inland waterways. Movements were defi ned 

as those to: 1) Kalama and Vancouver, WA, and Portland, OR, on the Columbia-Snake River system; 

2) Baton Rouge through New Orleans, LA, to the mouth of the passes on the Mississippi River system; 

3) Lake Charles, LA, on the Calcasieu River; 4) Mobile, AL, on the Tennessee-Tombigbee River system; 

5) Pascagoula, MS, on the Gulf Intracoastal Waterway; 6) Beaumont and Port Arthur, TX; 7) Galveston Bay 

(including Houston), TX; 8) Corpus Christi, TX, and the Gulf Intracoastal Waterway ports between Corpus 

Christi and the Mexican border; and 9) Hampton Roads and Norfolk, VA, on the Chesapeake Bay.

Barge Domestic. Domestic barge movements are calculated by subtracting export barge movements 

from total barge movements.

Truck Total. Total truck tonnages are estimated by subtracting total rail and total barge from total 

disappearance. The method for estimat ing truck grain tonnages and modal shares assumes that all 

barge and rail tonnages represent “long-haul” movements. “Short-haul” movements (farm-to-elevator) 

that originate on the farm are almost exclusively done by truck. Such farm-to-eleva tor movements 

are considered gathering movements. Unlike barge or rail move ments that typically end at the point of 

domestic consump tion or export, these truck movements represent only the fi rst and shortest segment of 

the en tire shipping route for grain. 

Truck Export. Truck export tonnages are estimated by subtracting rail export and barge export tonnages 

from total export tonnages.

Truck Domestic. Domestic truck tonnages are estimated by subtracting domestic rail and domestic 

barge tonnages from total domestic tonnages.
34

10

10 Bureau of Transportation Statistics, 2002. United States Department of Transportation, Atlas Databases 2002, CD-ROM: BTS.

Appendix B: FIPS Regions Included in Rail 

Export Tonnages10

State/country FIPS code County

Canada & Mexico 0 All areas

Alabama 1003 Baldwin

Alabama 1097 Mobile

Arizona 4023 Santa Cruz

California 6025 Imperial

California 6073 San Diego

Georgia 13051 Chatham

Georgia 13127 Glynn

Louisiana 22019 Calcasieu

Louisiana 22023 Cameron

Louisiana 22033 East Baton Rouge

Louisiana 22051 Jefferson

Louisiana 22063 Livingston

Louisiana 22071 Orleans

Louisiana 22075 Plaquemines

Louisiana 22089 St. Charles

Louisiana 22093 St. James

Louisiana 22095 St. John the Baptist

Louisiana 22121 West Baton Rouge

Minnesota 27137 St. Louis 

Mississippi 28045 Hancock

Mississippi 28047 Harrison

Mississippi 28059 Jackson

Ohio 39043 Erie

Ohio 39095 Lucas

Oregon 41009 Columbia

Oregon 41051 Multnomah

South Carolina 45019 Charleston

South Carolina 45053 Jasper

Texas 48061 Cameron

Texas 48141 El Paso

Texas 48167 Galveston

Texas 48201 Harris

Texas 48245 Jefferson

Texas 48323 Maverick

Texas 48355 Nueces

Texas 48361 Orange

Texas 48377 Presidio

Texas 48409 San Patricio

Texas 48479 Webb

Virginia 51710 Norfolk

Washington 53011 Clark

Washington 53015 Cowlitz

Washington 53033 King

Washington 53053 Pierce

Wisconsin 55031 Douglas

Wisconsin 55079 Milwaukee
35

Appendix C: Port Areas and 

Major City Ports

Port Area City State

Great Lakes

Burns Harbor IN

Chicago IL

Duluth MN

Milwaukee WI

Superior WI

Toledo OH

Mississippi River Gulf

Ama LA

Convent LA

Destrehan LA

Lutcher LA

Myrtle Grove LA

Paulina LA

Port Allen LA

Reserve LA

Westwego LA

Pacifi c Northwest

(PNW)

Fredrickson WA

Kalama WA

Moses Lake WA

Pasco WA

Portland OR

Seattle WA

Tacoma WA

Vancouver WA

Texas Gulf

Beaumont TX

Brownsville TX

Channelview TX

Corpus Christi TX

Galena Park TX

Galveston TX

Lake Charles LA

Note: Additional city ports are located in CA, AL, NY, VA, GA, NC, MD, and NJ.
36

Appendix D: Modal Share Information for

Other Crops

Year & 

type of 

movement

Mode of transport

Rail Barge Truck

1,000 tons Percent 1,000 tons Percent 1,000 tons Percent

Total

1995 5,070 34 1,442 10 8,606 57

1996 4,602 28 1,441 9 10,589 64

1997 5,801 30 1,257 7 11,972 63

1998 4,710 33 1,168 8 8,236 58

1999 5,222 35 1,333 9 8,557 57

2000 4,626 32 1,322 9 8,606 59

2001 4,633 37 1,335 11 6,478 52

2002 4,088 36 1,225 11 6,196 54

2003 2,098 19 1,365 12 7,555 69

2004 2,380 22 852 8 7,678 70

2005 2,430 24 721 7 7,164 69

2006 3,447 37 730 8 5,123 55

2007 3,446 30 1,252 11 6,919 60

Export

1995 2,202 36 1,430 23 2,471 41

1996 2,331 42 1,382 25 1,813 33

1997 3,074 53 1,247 22 1,447 25

1998 3,065 56 1,165 21 1,277 23

1999 4,197 67 1,331 21 782 12

2000 3,650 52 1,317 19 2,070 29

2001 3,880 58 1,326 20 1,513 23

2002 3,621 59 1,218 20 1,247 20

2003 1,784 32 1,362 25 2,401 43

2004 1,859 37 852 17 2,377 47

2005 2,005 40 721 14 2,334 46

2006 2,935 56 730 14 1,584 30

2007 2,992 47 1,246 19 2,156 34

Domestic

1995 2,868 32 12 0 6,135 68

1996 2,271 20 59 1 8,776 79

1997 2,728 21 10 0 10,525 79

1998 1,645 19 3 0 6,959 81

1999 1,025 12 2 0 7,775 88

2000 976 13 5 0 6,536 87

2001 753 13 8 0 4,965 87

2002 467 9 6 0 4,949 91

2003 315 6 3 0 5,155 94

2004 521 9 0 0 5,301 91

2005 425 8 0 0 4,831 92

2006 512 13 0 0 3,539 87

2007 453 9 6 0 4,763 91

Table 11: Tonnages and modal shares for U.S. sorghum, 1995-2007
37

Figure 20: U.S. sorghum export shipments by mode, 1995–2007

Figure 19: U.S. sorghum domestic shipments by mode, 1995–2007

0

2

4

6

8

10

12

14

1995 1996 1997 1998 1999 2000 2001 2002 2003 2004 2005 2006 2007

Million Tons

Year

Rail Barge Truck

0

2

4

6

8

10

12

14

95 96 97 98 99 00 01 02 03 04 05 06 07

Million Tons

Year

Rail Barge Truck
38

Year & 

type of 

movement

Mode of transport

Rail Barge Truck

1,000 tons Percent 1,000 tons Percent 1,000 tons Percent

Total

1995 6,509 69 690 7 2,195 23

1996 4,202 47 325 4 4,414 49

1997 3,928 48 541 7 3,772 46

1998 3,246 44 280 4 3,819 52

1999 3,586 51 307 4 3,099 44

2000 3,250 44 478 7 3,588 49

2001 2,952 44 204 3 3,535 53

2002 2,866 50 167 3 2,719 47

2003 3,432 63 196 4 1,790 33

2004 2,958 56 130 2 2,179 41

2005 2,855 54 207 4 2,208 42

2006 2,825 58 179 4 1,827 38

2007 2,796 50 247 4 2,504 45

Export

1995 701 51 574 42 94 7

1996 446 37 285 23 484 40

1997 854 48 457 26 458 26

1998 271 41 259 39 126 19

1999 409 58 287 41 8 1

2000 652 58 449 40 27 2

2001 585 62 171 18 189 20

2002 398 72 154 28 0 0

2003 501 73 183 27 0 0

2004 249 67 121 33 0 0

2005 589 70 159 19 91 11

2006 218 49 140 32 82 19

2007 627 75 206 25 0 0

Domestic

1995 5,808 72 116 1 2,102 26

1996 3,756 49 40 1 3,929 51

1997 3,075 48 84 1 3,314 51

1998 2,975 44 21 0 3,693 55

1999 3,177 51 20 0 3,091 49

2000 2,599 42 29 0 3,561 58

2001 2,367 41 33 1 3,347 58

2002 2,468 47 13 0 2,719 52

2003 2,931 62 13 0 1,790 38

2004 2,709 55 9 0 2,179 44

2005 2,266 51 48 1 2,117 48

2006 2,608 59 39 1 1,745 40

2007 2,170 46 41 1 2,504 53

Table 12: Tonnages and modal shares for U.S. barley, 1995-2007
39

Figure 22: U.S. barley export shipments by mode, 1995–2007

Figure 21: U.S. barley domestic shipments by mode, 1995–2007

0

1

2

3

4

5

6

7

8

9

1995 1996 1997 1998 1999 2000 2001 2002 2003 2004 2005 2006 2007

Million Tons 

Year

Rail Barge Truck

0

2

4

6

8

10

1995 1996 1997 1998 1999 2000 2001 2002 2003 2004 2005 2006 2007

Million Tons

Year

Rail Barge Truck
40

Photo Credits

USDA NRCS

USDA ARS

USDA ARS

USDA ARS

Magnus Rosendahl

USDA ARS

MorgueFile USDA ARS

U.S. Army Corps of 

Engineers

Gene Hanson USDA

Note: All photos 

credited here appear 

on the front cover of 

this publication.