Commodity Flow Survey (CFS) data

The U.S. commodity flow data, which is based on the 2007 Commodity Flow Survey (CFS) conducted by the Research and Innovative Technology Administration (RITA), Bureau of Transportation Statistics (BTS), and the U.S. Census Bureau, U.S. Department of Commerce, has been released recently in December 2009 and thus provides the fourth set of data on the movement of goods in the United States.

Table 2-3. Comparison among datasets of CFS 1993, 1997, 2002 and 2007

1993 1997 2002 2007 Industry coverage Based on 1987 SIC²⁾ Based on 1997 NAICS³⁾

Commodity 1) National Transportation Analysis Regions defined in a basis of the Bureau of Economic Analysis regions 2) Standard Industry Classification

3) North America Industry Classification System

4) Standard Transportation Commodity Classification; number in the parenthesis is based on 2-digit SCTG code 5) Standard Classification of Transported Goods; number in the parenthesis is based on 20digit SCTG code; from

the 2002 CFS, retail electronic shopping and mail-order houses are newly added

6) excludes “other and unknown modes”; figures include the number of single modes as well as multiple modes Note: Author summarized based on overview information for each CFS report

This study utilizes all the sets of commodity flow data based on the CFS since 1993 to identify the geographical patterns of U.S. interstate commodity flows over time, for 1993, 1997,

2002 and 2007. The CFS data provides information on shipment characteristics such as type, value, weight, distance, origins and destinations, and transportation modes for commodities shipped in the 50 states and the District of Columbia (D.C.). These state-to-state commodity flow movement information has been commonly used for regional transportation-related research and policy making although there are a couple of inherent problems. One main limitation is that some parts of the interstate commodity flow information in CFS data are not disclosed due to an unacceptably high statistical variability and the resulting lack of confidence in the estimate.

The other one would be due to the limited industry coverage of the survey. While the CFS covers shipments originating from mining, manufacturing, wholesale, and selected retail and services trade industries, commodity shipments from farms, fisheries, transportation, construction, and most government-owned establishments and many other retail and services industry-related establishments are excluded from the CFS. In order to overcome these limitations, the Office of Operations, Freight Management and Operations of the Federal Highway Administration (FWHA), U.S. Department of Transportation (USDOT) funded the Freight Analysis Framework (FAF) project, which developed a technique that fills gaps in the U.S. commodity flow matrices provided by CFS 2002⁴. However, the present study is based on CFS data instead of FAF² data since its main objective is to explore the spatial shifts in the U.S.

interstate commodity flows between 1993 and 2007; this would not be possible with the FAF data. This study focuses on 48 U.S. states that exclude Alaska and Hawaii. This study aggregates the given commodity categories in CFS into 13 groups that still preserves more detail in manufactured goods.

4 The FAF project constructed the U.S. commodity flow matrix mainly based on CFS 2002 and any other commodity flow datasets offering national, commodity specific, and mode specific coverage by employing two principal methods: the log-linear modeling and iterative proportional fitting (IPF) routines. The project produced the FAF 2002 U.S. Commodity Origin-Destination Database (FAF²), which is comprised of three four-dimension matrices for tons, value, and ton-miles, in which the four dimensions are origin, destination, commodity, and mode.

Table 2-4. Commodity classification for CFS analysis in this study

code Sector description SCTG (1997, 2002, 2007) STCC (1993) 01 Agriculture, Forestry and Fisheries 1-4, 25 1, 8-9

02 Mining 10-16 10-11, 13-14

03 Construction None None

04 Food, Beverage, and Tobacco Products 5-9 20, 21 05 Textile, Apparel, and Leather Products 30 22, 23, 31 06 Paper and Printing Related Products 27, 28, 29 26, 27 07 Chemical and Allied Products 17-24, 31 28-30, 32

08 Primary Metals Products 32 33

09 Fabricated Metal Products 33, 38 19, 34, 38

10 Industrial Machinery and Equipment 34 35

11 Electronic and Electric Equipment 35 36

12 Transportation Equipment 36, 37 37

13 Wood, Furniture & Misc. Manufacturing Products 26, 29, 40 24, 25, 39 14 TCU, Services, and Government Enterprises 41, 43, 99 40, 41, 42, 48, 99 Note: No commodities shipped in the sector of construction (03)

All the analyses in this study are basically conducted for all aggregated commodities and with greater attention to the values of shipments. However, the analysis based on tonnage of shipment will be conducted to enhance the insights in the pattern and structure of flows.

Further, some selected commodity groups are also considered for the deeper analysis. Related to the commodity-specific flows, selected manufactured goods such as chemical products and food, beverage and tobacco products explain the large part of the whole comprehensive flows.

Another selected commodity group is the goods from mining industry since this commodity group also accounts for a large amount of shipments in terms of value as well as weight. For instance, chemical products and food-beverage-tobacco products account for over 30% of the values of all commodity shipments (24.1% and 8.8%, respectively), and mining products comprise 30.1% of all tons shipped among 48 U.S. states in 2007.

Table 2-5. Value of shipment by commodity group, 1993, 1997, 2002, and 2007 (unit: million $)

1993 1997 2002 2007

commodity Value Rank Value Rank Value Rank Value Rank

01 125762 11 187157 11 114311 11 251953 11

Note 1: Only 48 U.S. states are considered for calculations.

Note 2: For the rankings, sector 13 and 14 are excluded since their composition characteristics.

Data source: Bureau of Transportation Statistics, Commodity Flow Survey 1993, 1997, 2002 and 2007

Table 2-6. Tonnage of shipment by commodity group, 1993, 1997, 2002, and 2007 (unit: thousand tons)

1993 1997 2002 2007

Commodity Ton Rank Ton Rank Ton Rank Ton Rank

01 525984 4 966203 3 504135 3 790010 3

Note 1: data calculated for 48 U.S. states Note 2: ranking for sector 13 is not considered

Data source: Bureau of Transportation Statistics, Commodity Flow Survey 1993, 1997, 2002 and 2007

2.2. Exploratory spatial data analysis of interstate commodity flows