Import/Export Price Indexes • mxpinfo@bls.gov • www.bls.gov/mxp • (202) 691-7101

www.bls.gov

Measuring Price Change for Inbound Crude Oil Tanker 

Freight in the U.S. Import/Export Price Indexes

The Bureau of Labor Statistics (BLS) Inbound Crude Oil 

Tanker Freight Index measures changes in the average 

price charged for delivery of crude oil on tanker freight 

vessels to the U.S. The tanker index was first published 

in 1987 with a lag of one quarter. In 2001, BLS began 

calculating the index monthly, published with a two 

month lag. This index was discontinued in 2008. BLS 

publishes international services price indexes for air 

freight and air passenger fares. Historical data are 

available for crude oil tanker freight and ocean liner 

freight (http://www.bls.gov/web/discsrv.htm), 

education (http://www.bls.gov/web/srv3.htm) and 

travel and tourism services 

(http://www.bls.gov/web/srv2.htm). 

Crude oil tanker freight consists of bulk crude oil 

shipments measured in barrels. Other liquids 

transported in tankers, such as chemicals and liquid 

natural gas, are not included in this index. The scope of 

the service measured is ocean transportation; 

therefore, the service being priced is from port to port 

only, and does not include any ground transportation or 

port service. 

The Inbound Crude Oil Tanker Freight Index reflects 

changes in rates paid for the transportation of crude oil 

loaded from foreign countries and shipped to the U.S. 

on tanker vessels regardless of the nationality of either 

the shipper or the vessel operator/owner. This BLS 

index captures inbound shipments only. The U.S. 

Department of Commerce’s Bureau of Economic 

Analysis (BEA) is the primary user of the BLS 

import/export and inbound transportation services 

indexes. BEA uses these indexes to adjust the Balance 

of Payments Accounts and to deflate the gross domestic 

product (GDP). 

Sample Design and Selection 

The Inbound Crude Oil Tanker Freight Index comprises 

the entire universe of tanker transactions reported to 

the U.S. Department of Energy (DOE). BLS receives a 

monthly file from DOE that includes data on all reported 

petroleum and tanker transactions into the U.S. over 

the previous period. This file is used to calculate both 

the Inbound Crude Oil Tanker Index and the 

Import/Export Crude Petroleum Index. 

The Inbound Crude Oil Tanker Index is published in a 

lagged manner due to the availability of the data from 

DOE. The index is lagged by two months. The three 

previous months’ index values are revised each period 

to capture all new data reported by the tanker 

companies to DOE in the intervening months. For 

example, the January tanker price index is published 

with the release of March import/export price indexes, 

and the tanker index numbers for October, November, 

and December also are recalculated at this time to 

reflect the most current data. 

Pricing 

The tanker index is an average price index. A weighted 

average of transactions sharing trade routes is used for 

comparison each month rather than comparing single 

transactions. Each tanker item is defined by 

transactions of the same region of origin and delivery. 

One item, for example, includes all tanker freight 

transactions from the Middle East to the U.S. Gulf of 

Mexico. For each item, the average price of all 

transactions delivered in a given month is compared 

over time. Transactions within each item are weighted 

by quantity of barrels and price per barrel. 
Import/Export Price Indexes • mxpinfo@bls.gov • www.bls.gov/mxp • (202) 691-7101

www.bls.gov

Measuring Price Change for Inbound Crude Oil Tanker 

Freight in the U.S. Import/Export Price Indexes

Trade Value Weights 

The revenue weights used for index calculation are 

derived from a regression analysis based on one year’s 

worth of tanker transactions from DOE. Trade value 

weights are updated every five years and currently 

reflect year 2005 dollar values. 

Additional Information 

Additional information on the U.S. Import/Export Price 

Indexes can be found in “International Price Indexes,” 

BLS Handbook of Methods, Bulletin 2490 (Bureau of 

Labor Statistics, 1997), Chapter 15. This chapter also is 

available on the BLS Internet site 

(http://www.bls.gov/mxp) under the topic 

"Publications." You may contact the International Price 

Program of BLS by telephone at (202) 691-7101 or by email at mxpinfo@bls.gov. 

Information in this report is in the public domain and 

may be reproduced without permission. This 

information is available to sensory impaired individuals 

upon request. Voice phone: (202) 691-5200; TDD 

Federal Relay Service: 1-800-877-8339. 

Last Modified Date: December 12, 2011