The U.S. Census Bureau conducts the Advance Monthly Retail Trade and Food Services Survey (MARTS) to provide an early estimate of monthly sales by kind of business for retail and food service firms located in the United States.

Each month, questionnaires are mailed to a probability sample of approximately 5,000 employer firms selected from the larger Monthly Retail Trade Survey (MRTS). Firms responding to MARTS account for approximately 65% of the total national sales estimate. Advance sales estimates are computed using a link relative estimator. The change in sales from the previous month is estimated using only units that have reported data for both the current and previous month. There is no imputation or adjustment for non-respondents in MARTS. The total sales estimate is derived by multiplying this ratio by the preliminary sales estimate for the previous month (derived from the larger MRTS sample). Detailed industry estimates are summed to derive total estimates at broad industry levels. The monthly estimates are adjusted using annual survey estimates and for seasonal variation and holiday and trading-day differences.