Food Use Estimates
Estimating Domestic Food Use
Domestic food use of wheat must be estimated indirectly because no data are collected on actual consumption of wheat in the United States. Estimates are made monthly. The estimate is the sum of wheat milled for flour, net imports (imports minus exports) of flour and wheat products (wheat products used for food only; products used for feed are excluded), and nonflour wheat use (grain processed in some way other than milling). The data on flour produced is from the North American Millers’ Association (NAMA). The data on imports and exports are from the Department of Commerce, Census Bureau. The estimate for nonflour wheat food use is made by ERS.
ERS estimates food-use data for for each of the five classes of U.S. wheat: hard red winter, hard red spring, soft red winter, white, and durum. The flour and wheat products included in the trade estimates are items for food use only; feed items are excluded. These estimates are then vetted by the various agencies in USDA's wheat Interagency Commodity Estimates Committee.
Historical Relationships are Used to Estimate Wheat Milled Each Month
NAMA publishes quarterly data on the quantity of wheat flour produced in the United States. The quarterly flour data are used by ERS to estimate the quantity of wheat milled each month. The monthly estimates are based on relationships developed from factors to estimate monthly wheat milled from Census quarterly wheat milled data (from 1990-97, the Census Bureau published the quantity of wheat milled each month, but discontinued the series after 1997). To estimate each month's quantity of wheat milled, the ERS quarterly number is multiplied by that month's historical share of 1990-97 quarterly data.
Nonflour Use of Wheat
The ERS estimate of monthly nonflour use (for example, whole wheat grain added to bread) is currently 2 million bushels per month. This estimate was developed in consultation with industry representatives. Nonflour use is added to the wheat milled total (adjusted for trade) to obtain an ERS estimate of the total use of wheat for food by month.
Because there is no estimate of nonflour use of durum wheat, it is omitted from the calculation of durum food use.
All flours, but only selected wheat food products, are used in estimating wheat trade quantities for total wheat and durum wheat. The selected food products included in the estimates are based on relative volumes traded.
- Imports: Hard red spring, durum, white winter, semolina, and flour not elsewhere specified
- Exports: Wheat flour and semolina
- Imports: Pasta made with eggs, pasta made without eggs, couscous, and bulgur
- Exports: Pasta made with eggs, pasta made without eggs, couscous, and bulgur
The Bureau of Census publishes monthly data on imports and exports of flour and wheat products. The data are categorized by the Harmonized Tariff Schedule (HTS) of the United States. For more information on HTS codes and agricultural trade data, see Foreign Agricultural Trade of the United States (FATUS): Questions and Answers.
Converting Census Data to Grain-Equivalent Bushels
The census trade data for grain, flour, and selected products are in metric tons (grain exports) or kilograms (flour and products). The flour and selected products are converted to grain-equivalent kilograms--i.e., the quantity of wheat grain that would have to be milled to produce 1 kilogram of that flour or wheat product. Then, the grain and grain-equivalent data are converted to bushels. The factors for the conversion are 2.204622 pounds per kilogram and 60 pounds per bushel.
An example calculation converting 1.0 million kilograms of flour to grain-equivalent bushels is as follows:
Step 1. Converting kilograms of hard spring flour to grain-equivalent kilograms:
1,000,000 kilograms * 1.36986 = 1,369,860 kilograms
Step 2. Converting grain-equivalent kilograms to grain-equivalent pounds:
1,369,860 kilograms * 2.204622 pounds/kilogram = 3,020,023.493 pounds
Step 3. Converting grain-equivalent pounds to grain-equivalent bushels:
3,020,023.493 pounds * 1 bushel/60 pounds = 50,334 bushels
Once all the data for flour and products are in grain-equivalent bushels, the net of the export and import totals is added to the estimates for wheat milled and nonflour use.
Estimate of wheat milled (in bushels)
+ Estimate of wheat flour and products imported (in grain-equivalent bushels)
- Estimate of wheat flour and products exported (in grain-equivalent bushels)
+ ERS estimate of nonflour use of wheat (in grain-equivalent bushels)
= Estimate of apparent food use of wheat
For the durum food use estimate, the calculation does not include a nonflour use estimate.
Details on the HTS codes and the conversion factors used to estimate trade are provided in Excel spreadsheets: