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Monthly Wholesale Trade

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What is a sample revision and why is it necessary?

A sample revision is the process used to re-design and re-select the samples for the Census Bureau's surveys of the retail, wholesale, and service industries. This process is performed to:

  • improve the efficiency of each sample
  • incorporate updates to the industry classification structure
  • expand industry coverage of the survey
  • update questions and instructions to obtain more accurate data, and
  • redistribute burden for small and medium size businesses.

The current Monthly Wholesale Trade Survey sample was introduced with the release of estimates for March 2018 on May 25, 2018.

How often is a sample revision performed for the Monthly Wholesale Trade Survey?

Sample revisions are performed approximately every 5 to 7 years. During the period for which the samples are used, updates are made on a quarterly basis to reflect changes in the business universe. These updates are designed to account for new businesses (births) and businesses which discontinue operations (deaths). The samples are also updated to reflect mergers, acquisitions, divestitures, splits, and other changes to the business universe.

What is the size of the Monthly Wholesale Trade Survey sample?

The size of the current Monthly Wholesale Trade Survey sample is approximately 4,200 employer firms. The size of the prior Monthly Wholesale Trade Survey sample was also approximately 4,200 employer firms.

Are the estimates from the prior and new samples comparable?

In most cases, yes. Whenever possible, estimates from the prior and new samples have been put on a comparable basis. For a detailed description of the process used to link the estimates from the prior and new samples and for specific information on which industry estimates are not comparable, please refer to https://www.census.gov/wholesale/pdf/mwts/methods/MWTS_Stratification.pdf.

What is the impact of adopting the 2012 North American Industry Classification System (NAICS) definitions for the Monthly Wholesale Trade Survey?

The new sample was designed with the 2012 NAICS definitions in mind. All estimates on the new sample are in terms of those definitions. In order to have consistent time series, all estimates from prior samples, that were in terms of 2007 NAICS definitions were restated to be in terms of 2012 NAICS definitions. For MWTS, only estimates for NAICS 4236 and 4237 were changed. For more information on NAICS, please see https://www.census.gov/eos/www/naics/.


Source: U.S. Census Bureau | Economic Indicators Division |   Last Revised: June 16, 2022