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 on a monthly basis. The estimate is the sum of
wheat milled for flour, net imports (imports minus exports) of flour
and wheat products (only wheat products used for food, products used
for feed are excluded), and nonflour wheat use (grain processed in
some way other than milling). The data on flour milling, imports,
and exports are from the Department of Commerce, Bureau of the Census.
The estimate for nonflour wheat use is made by ERS.
ERS estimates food-use data for both total wheat and for durum
wheat. Total wheat includes all 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
only items for food use; 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
Census publishes quarterly data (in bushels) on the quantity of
all wheat and durum wheat milled in the United States. Quarterly
data are used 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,
Census published the quantity of wheat milled each month; this was
discontinued after 1997). To estimate each month's quantity
of wheat milled, the Census 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.
Flour and Selected Products Used in Developing Wheat Trade Estimates
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.
| Wheat flour and selected products |
| Item |
Imports |
Exports |
| Flour |
Hard red spring, durum, white winter, semolina, and flour
not elsewhere specified |
Wheat flour and semolina |
|
Products |
Pasta made with eggs, pasta made without eggs, couscous,
and bulgur |
Pasta made with eggs, pasta made without eggs, couscous,
and bulgur |
| Durum flour and selected products |
| Item |
Imports |
Exports |
| Flour |
Durum flour and semolina |
Semolina |
|
Products |
Pasta made without eggs and couscous
(80 percent of this volume
of this pasta is assumed to be made from durum) |
Couscous and pasta made without eggs |
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 one 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:
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