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The Commodity Flow Survey (CFS) is the U.S. federal survey of domestic freight shipments made by American businesses. Researchers use it to study what is shipped, how much it weighs and is worth, where it goes and by which transport mode. This guide sets out who runs it, how it samples establishments, what it measures and how to find and cite its data, as described on the official Census Bureau CFS pages.
What it is and who runs it
A commodity flow survey, in the U.S. sense, is the CFS: a joint effort of the Bureau of Transportation Statistics (BTS) in the U.S. Department of Transportation and the U.S. Census Bureau in the Department of Commerce. Census describes it as the primary source of national and state-level data on domestic freight shipments by American businesses. It is shipper-based: the unit that reports is the business establishment that sends goods, not the carrier that moves them.
The survey covers establishments in Mining, Manufacturing, Wholesale Trade, select Retail and Services industries, and some auxiliary establishments such as warehouses. It does not include imports or shipments originating in U.S. territories.
Sampling design
Establishments are selected by geographic location and industry. For the 2022 survey, Census reports a sample of 165,000 establishments. Each sampled establishment reports either a sample of its shipments or all of them for a specified one-week period in each calendar quarter, so the data reflect four reporting weeks spread across the year rather than a continuous record. From the 2022 survey, respondents report through a secure online portal. For background on how stratification and weighting underpin designs like this, see stratified sampling and survey weighting.
What the CFS measures
- Shipment value and weight
- Origin and destination
- Commodity type
- Transportation mode, including exports
When one shipment contains several commodities, respondents report the commodity that makes up the greatest percentage of the shipment’s weight, so mixed shipments are classified by their heaviest commodity. Published tables use the Standard Classification of Transported Goods (SCTG) and NAICS industry codes, cross-classified by mode and by origin and destination geography (U.S., region, division, state and CFS area).
Is data considered a commodity?
Not in this survey. The CFS measures physical goods that establishments ship, classified by SCTG commodity group. Whether data is a commodity in an economic sense is a separate question the survey does not address.
What is the Census HS code, and how does it differ from the CFS classification?
The Harmonized System (HS) is a trade classification used for goods crossing borders, and it is a different system from the SCTG codes used to publish CFS tables. If you are matching CFS commodity groups to trade data, treat the two schemes as separate classifications that need a crosswalk. For the export-filing side of HS numbers, see HS code vs Schedule B.
What is the commodity flow approach?
“Commodity flow approach” is a general phrase for analysing freight by tracing commodities between origins and destinations. It is a way of framing analysis, not the name of the survey; the CFS is one federal data source such analyses can draw on.
Eligibility: who is surveyed
Establishments are selected by geographic location and industry within the covered sectors (Mining, Manufacturing, Wholesale Trade, select Retail and Services industries, and some auxiliary establishments such as warehouses). Researchers who only want to use the data have no eligibility requirement; the published products are public.
What it requires: the response obligation
For sampled establishments, the survey is authorized by Title 13, U.S.C., Section 131, and Sections 224 and 225 require recipients to respond. Under Section 9 the information is confidential and used only for statistical purposes. Respondents report shipment value, weight, origin, destination, commodity and mode, and from the 2022 survey they report through a secure online portal.
Steps to obtain and use the data
- Open the Census CFS data page and choose the product type: microdata, tables or experimental products.
- For the 2022 survey, download the PUMS file, the data dictionary and the PUMS user’s guide from the dataset page.
- Read the user’s guide before analysis, because it defines the file’s fields.
- Match commodity and industry fields to SCTG and NAICS codes, and geography to the CFS area definitions.
- Cite the file using the wording on the dataset page you downloaded from.
Common mistakes
- Treating the CFS as a count of all freight: it excludes imports and shipments originating in U.S. territories.
- Assuming mixed shipments are split by commodity: each is classified by the commodity with the greatest share of weight.
- Mixing up SCTG commodity groups with Harmonized System trade codes without a crosswalk.
- Over-reading very small cells: published values are noise-infused, sample-based estimates, not exact company records.
- Assuming a continuous record: the data reflect four reporting weeks, not every day of the year.
Data products and how researchers access them
Census lists three kinds of CFS products on its data page:
| Product | What it is |
|---|---|
| Datasets | Microdata with personally identifiable information removed |
| Tables | Downloadable tables (CSV, spreadsheet or PDF), each with a release date |
| Experimental data products | Includes an experimental Public Use File giving shipment-level characteristics while protecting business confidentiality |
For the 2022 survey, Census’s dataset page lists a Public Use Microdata Sample (PUMS) file as a zipped CSV (about 680 MB), a data dictionary in Excel and a PUMS user’s guide in PDF. Read the user’s guide before analysis, because it defines the file’s fields.
Confidentiality and what it means for analysis
The survey is authorized by Title 13, U.S.C., Section 131, Sections 224 and 225 require recipients to respond, and under Section 9 the information is confidential and may be used only for statistical purposes. Census adds noise infusion as disclosure avoidance to disguise specific companies. For analysts, that means published values are protected estimates rather than exact company records, so very small cells deserve caution. Sample-based estimates also carry coverage and sampling error; see sampling frame and coverage error.
How to cite the CFS
Census’s suggested citation for the 2022 PUMS file credits the U.S. Department of Transportation’s Bureau of Transportation Statistics and the U.S. Department of Commerce’s Census Bureau, followed by the date (2026-01), the title “2022 Commodity Flow Survey Datasets: 2022 CFS Public Use Microdata Sample (PUMS) File” and the date you accessed the file. Copy the current wording from the dataset page you download from, since citation text can be updated.
Related programs
| Source | Relationship to the CFS |
|---|---|
| Census CFS program page | Official description of design, sponsors and confidentiality |
| Census CFS data page | Datasets, tables and experimental products |
| Sampling vs census | Explains why a survey like the CFS samples establishments rather than counting every shipment |
FAQ
What is a commodity flow survey?
It is the federal survey, run jointly by BTS and the Census Bureau, that samples establishments to estimate domestic freight shipments by value, weight, origin, destination, commodity and mode.
Does the CFS cover imports?
No. Census states that it does not include imports or shipments originating in U.S. territories; exports are included.
Who must respond?
Sampled establishments are required to respond; Title 13, U.S.C., Sections 224 and 225 require recipients to respond and return the report.
Where do I get the data?
From the Census Bureau’s CFS data page: datasets, downloadable tables and experimental products. See also survey research methods for general background.
Sources
- U.S. Census Bureau, Commodity Flow Survey: About, https://www.census.gov/programs-surveys/cfs/about.html (page revised 2025-06-26; checked 2026-11-07)
- U.S. Census Bureau, Commodity Flow Survey: Data, https://www.census.gov/programs-surveys/cfs/data.html (revised 2025-05-20; checked 2026-11-07)
- U.S. Census Bureau, 2022 CFS Datasets, https://www.census.gov/data/datasets/2022/econ/cfs/historical-datasets.html (checked 2026-11-07)
