2007 Commodity Flow Survey
Definitions of Key CFS Terms

Auxiliary establishment - An auxiliary establishment is an establishment primarily involved in rendering support services for other establishments within the same corporation, such as warehouses, distribution centers and central administrative offices. Auxiliary establishments with shipping activity were included in the CFS.

Average miles per shipment - Average miles per shipment were computed by dividing the total miles traveled by the total number of shipments.

Business register - The Census Bureau's Business Register is a database of all known establishments located in the United States or its territories, where an establishment is defined as a single physical location where business transactions take place or services are performed. The CFS sample was selected from the approximately 754,000 eligible establishments on the Business Register. Eligible establishments consisted of those classified as mining, manufacturing, wholesale, electronic shopping and mail-order houses, fuel dealers, and publishers.

Cell suppression - Cell suppression is used in CFS tables for two purposes: (1) protecting sensitive cells posing disclosure risks as indicated with a ‘D', and; (2) masking estimates of poor data quality or otherwise not meeting publication standards. The second form of suppression is often the result of high sampling variability and is represented by an ‘S' in the respective cell.

Coefficient of variation (CV) - See Sampling error

Commodity - Products that an establishment produces, sells, or distributes. This does not include items that are considered as excess or waste of the establishment's operation. Respondents reported the description and the five-digit Standard Classification of Transported Goods (SCTG) code for the commodity contained in the shipment. Shipments involving multiple commodities are classified as the commodity with the greatest weight in the total shipment.

Confidentiality - In accordance with Title 13 of the United States Code, no estimates are published that would disclose the operations of an individual firm. Title 13 authorizes the Census Bureau to conduct censuses and surveys. Section 9 of the same Title requires that any information collected from the public under the authority of Title 13 be maintained as confidential. Section 214 of Title 13 and Sections 3559 and 3571 of Title 18 of the United States Code provide for the imposition of penalties of up to 5 years in prison and up to $250,000 in fines for wrongful disclosure of confidential census information.

Disclosure avoidance - Disclosure is the release of data that have been deemed confidential. It generally reveals information about a specific individual or establishment and/or permits deduction of sensitive information about a particular individual or establishment. Disclosure avoidance is the process used to protect the confidentiality of the survey data provided by an individual or firm. For the CFS, the primary method of disclosure avoidance is Noise Infusion: Noise infusion is a method of disclosure avoidance in which values for each shipment are perturbed prior to tabulation by applying a random noise multiplier. Disclosure protection is accomplished in a manner that causes the vast majority of cell values to be perturbed by at most a few percentage points. In certain circumstances, some individual cells may be suppressed on a case by case basis for additional disclosure avoidance. In these cases the data are replaced with a "D" in the tables.

Estimates - Data in CFS tables reflect survey estimates, that is, these numbers and percentages are estimated totals produced using the sum of weighted shipment data (reported or imputed). CFS respondents provided data for a sample of shipments made by their respective establishments in the survey year. For each establishment, an estimate of that establishment's total value of shipments was produced for the entire survey year. To do this, four different weights were used - the shipment weight, the shipment nonresponse weight, the quarter weight, and the quarter nonresponse weight. Three additional weights were then applied to produce estimates representative of the entire universe - the establishment-level adjustment weight, the establishment (or sample) weight, and the industry-level adjustment weight.

Great circle distance - The shortest distance between two points on the surface of a sphere over the surface of that sphere.

Intermodal shipment - For the CFS, an intermodal shipment is defined as a shipment of a commodity that has been placed within a piece of transportation equipment that is designed to be interchanged (transferred) between different modes of transportation under a single rate (e.g., a single bill of lading). Examples of intermodal transportation include the shipment of commodities in truck trailers designed to be placed on railroad flat cars (TOFC); shipping containers designed to be placed on railroad flat cars (COFC); or shipping containers for marine transportation. Intermodal (IM or ISO) tanks designed for interchange between the truck, rail and marine modes are also examples of intermodal transportation reportable in the CFS. [Note: Although an attempt was made to identify intermodal shipments in the 2007 CFS, the data were not published due to quality issues.]

Mode of transportation - The type of transportation used for moving the shipment to its domestic destination. (For exports, the domestic destination was the port of exit.)

In the instructions to the CFS survey respondent, the possible modes of transportation were defined as follows:

Parcel delivery/Courier/U.S. Parcel Post - Included ground and air shipments of packages and parcels that each weighed less than 100 pounds, and were transported by a for-hire carrier.

Private truck - Trucks operated by employees of the establishment or the buyer/receiver of the shipment, including trucks providing dedicated services to the surveyed establishment.

For-hire truck - Shipments made by common or contract carriers under a negotiated rate.

Railroad - Any common carrier or private railroad.

Shallow draft vessel - Barges, ships, or ferries operating on rivers and canals; in harbors, the Great Lakes, the Saint Lawrence Seaway, the Intracoastal Waterway, the Inside Passage to Alaska, major bays and inlets, or in the ocean close to the U.S. shoreline.

Deep draft vessel - Barges, ships, or ferries operating primarily in the open ocean. (Shipping on the Great Lakes and the Saint Lawrence Seaway is classified with shallow draft vessels.)

Pipeline - Movements of oil, petroleum, gas, slurry, etc. through pipelines that extend to other establishments or locations beyond the shipper's establishment, excluding aqueducts for the movement of water.

Air - Any individual package shipped by air that weighed 100 pounds or more.

Other mode - Any mode not listed above.

Unknown - Any shipment where the mode of transportation could not be determined.

[Note: Transportation equipment that is "shipped" under its own power, such as boats, barges, ferries, ships, aircraft, trucks, and trains should be classified with the appropriate mode above. Transportation equipment shipped under its own power for which an appropriate mode is not listed (e.g., buses, recreational vehicles) should be listed as "other" mode.]

Terms used in the tables for mode of transport:

Air (includes truck and air) - Shipments that used air or a combination of truck and air.

Single modes - Shipments transported by only one of the above-listed modes, except parcel or other and unknown.

Multiple modes - Shipments for which two or more of the following modes of transportation were used:

    • Private truck
    • For-hire truck
    • Railroad
    • Shallow draft vessel
    • Deep draft vessel
    • Pipeline

In addition, Parcel, U.S. Postal Service, or Courier shipments are considered multiple modes because this category includes all parcel shipments whether on the ground or via air tendered to a parcel or express carrier. In defining this mode, we did not combine these shipments with any other reported mode because by their nature, Parcel, U.S. Postal Service or Courier are already multimodal. For example, if the respondent reported a shipment's mode of transportation as "parcel" and "air," we treated the shipment as parcel only. Also in the CFS reports, the "Truck and Rail" and "Rail and Water" combinations included under "Multiple Modes" may not reflect all the movement of trailers or containers by rail and at least one other mode of transportation. Since the shipper may not always know the modal combinations used to transport the goods, some shipments moving by more than one mode may be reported as a single mode shipment. This may result in underestimation of multimodal shipments in the CFS.

Other multiple modes - Shipments using any other mode combinations not specifically listed in the tables.

Other and unknown modes - Shipments for which modes were not reported, or were reported by the respondent as "Other" or "Unknown."

Truck - Shipments using for-hire truck only, private truck only, or a combination of for-hire truck and private truck.

Water - Shipments using shallow draft vessel only, deep draft vessel only, or Great Lakes vessel only. Combinations of these modes, such as shallow draft vessel and Great Lakes vessel are included as "Other multiple modes." (Note: By definition, "shallow draft," "Great Lakes," and "deep draft" are mutually exclusive.)

Great Lakes - In the tables, "Great Lakes" appears as a single mode.

North American Industry Classification System (NAICS) - The North American Industry Classification System (NAICS) is the standard used by Federal statistical agencies in classifying business establishments for the purpose of collecting, analyzing, and publishing statistical data related to the U.S. business economy. NAICS was developed under the auspices of the Office of Management and Budget (OMB), and adopted in 1997 to replace the Standard Industrial Classification (SIC) system. NAICS groups industries into 20 broad sectors (as opposed to 10 sectors under SIC), identified by a 6-digit code (SIC had a 4-digit code) and is based on the type of the establishment, not the type of commodity. The SIC was used in conducting the 1993 and 1997 CFS; however, the 2002 and 2007 CFS used the NAICS. [Note: NAICS is a hierarchical classification system. A 2-digit NAICS code identifies an industry sector, the 3rd digit identifies the subsector, the 4th digit designates the industry group…and the 6-digit code indentifies a specific industry. There are currently 1,170 industries designated in the NAICS. See (link to NAICS site) for more information about the NAICS.]

Sampling error - Because CFS estimates are produced from a sample survey (as opposed to the complete enumeration of all shipments made in 2007 from all establishments,) a measure of sampling error is likewise estimated and provided for all estimates shown in tables. Common measures related to sampling error are the sampling variance, the standard error, and the coefficient of variation (CV). The sampling variance is the squared difference, averaged over all possible samples of the same size and design, between the estimator and its average value. The standard error is the square root of the sampling variance. The CV expresses the standard error as a percentage of the estimate to which it refers. In the CFS tables, we use CVs to express the sampling error of estimates for shipment characteristics (values, tons, ton-miles, and average miles per shipment) whereas standard errors are provided for percentages (where calculated).

Shipment - A shipment is a single movement of goods, commodities, or products from an establishment to a customer or to another establishment owned or operated by the same company as the originating establishment (e.g., a warehouse, distribution center, or retail or wholesale outlet). Full or partial truckloads are counted as a single shipment only if all commodities on the truck are destined for the same location. If a truck makes multiple deliveries on a route, the goods delivered at each stop are counted as one shipment. Interoffice memos, payroll checks, or business correspondence are not considered shipments. Shipments such as refuse, scrap paper, waste, or recyclable materials are not considered shipments unless the establishment is in the business of selling or providing these materials.

Standard Classification of Transported Goods (SCTG) - The commodities shown in this report are classified using the SCTG coding system. The SCTG coding system was developed jointly by agencies of the United States and Canadian governments based on the Harmonized Commodity Description and Coding System (Harmonized System) to address statistical needs in regard to products transported. The SCTG employs a five-digit numbering system, the structure of which is hierarchical consisting of four levels. (See (link to SCTG site) for more information on the SCTG coding system.) The SCTG system was used in the 1997, 2002, and 2007 iterations of the CFS; the Standard Transportation Commodity Code (STCC) coding scheme maintained by the Association of American Railroads was used in the initial CFS in 1993.

Third-party logistics provider (3PL) - An outsourced provider that manages and provides all or a significant part of an organization's warehousing and transportation needs. A 3PL provides under contract some or all of these functions: management of transportation; warehousing; transportation; inventory control; and order management. Companies that provide only trucking services or only warehousing services are not considered 3PLs.

Ton-miles - The shipment weight multiplied by the mileage traveled by the shipment. The respondents reported shipment weight in pounds. Aggregated pound-miles were converted to ton-miles. Mileage was calculated as the distance between the shipment origin and destination ZIP Codes. For shipments by truck, rail, or shallow draft vessels, the mileage excludes international segments. For example, mileages from Alaska to the continental United States exclude any mileages through Canada (see the "Mileage Calculations" section for more details). For trucks making multiple stops, the ton-miles are calculated for each delivery, and each drop-off point is treated as a final destination. Ton-miles estimates are displayed in millions.

Tons shipped - The total weight of the entire shipment. Respondents reported the weight in pounds. Aggregated pounds were converted to short-tons (2,000 pounds). The ton totals in the CFS represent the sum of separate shipments of a commodity as it moves through the production and consumption segments of the supply chain; hence the tonnage of goods may be counted more than once in the production life cycle (e.g., goods that are moved through distribution centers).

Total modal activity (as reported in CFS Table 2) - Refers to the values for the overall activity (e.g., ton-miles) of a specific mode of transportation. It includes shipments made with a particular mode, whether used as single-mode shipment, or as part of a multiple-mode shipment. For example, the total modal activity for private truck is the total ton-miles carried by private truck in single-mode shipments, combined with the total ton-miles carried by private truck in all multiple-mode shipments that include private truck (private truck and for-hire truck, private truck and rail, private truck and air, etc.)

Value of shipments - The dollar value of the entire shipment. This was defined as the net selling value, exclusive of freight charges and excise taxes. The value data are displayed in millions of dollars. The total value of shipments, as measured by the CFS, and the U.S. gross domestic product (GDP) provide different measures of economic activity in the United States and are not directly comparable. GDP is the value of all goods produced and services performed by labor and capital located in the United States. The value of shipments, as measured by the CFS, is the market value of goods shipped from manufacturing, mining, wholesale, and select retail and service establishments, as well as warehouses and managing offices of multiunit establishments. Three important differences between GDP and value of shipments:

  1. GDP captures goods produced by all establishments located in the United States, while CFS measures goods shipped from a subset of all goods-producing establishments.
  2. GDP measures the value of goods produced and of services performed. CFS measures the value of goods shipped.
  3. GDP counts for only the value-added at each step in the production of a product. CFS captures the value of shipments of materials used to produce or manufacture a product, as well as the value of shipments of the finished product itself. This means that the value of the materials used to produce a particular product contributes multiple times to the value of the commodity in the CFS.