United States 

Department 

of Agriculture 

www.ers.usda.gov 

 A Report from the Economic Research Service

Paul C. Westcott, westcott@ers.usda.gov

Jerry D. Norton, jnorton@oce.usda.gov

Implications of an Early Corn 

Crop Harvest for Feed and 

Residual Use Estimates

FDS-12f-01

July 2012

Contents

Approved by USDA’s 

World Agricultural 

Outlook Board

Introduction . . . . . . . . . . . . . . . 3

Feed and Residual Usage 

Balances Corn Supply and 

Demand . . . . . . . . . . . . . . . . . . . 4

Potential Effects of an Early 

Corn Harvest . . . . . . . . . . . . . . . 6

Feed and Residual Use 

Model . . . . . . . . . . . . . . . . . . . . 7

Model Results and Selected 

Model Properties . . . . . . . . . . 13

Implications of an Early 

2012 Corn Harvest . . . . . . . . . 17

Conclusions . . . . . . . . . . . . . . . 18

References . . . . . . . . . . . . . . . . 19

Appendix—Impacts of 

Early New-Crop Usage on a 

Supply-and-Demand 

Balance Sheet . . . . . . . . . . . . . 20

Abstract

U.S. corn plantings this spring were ahead of a typical pace, suggesting that prospects 

may be good for an early harvest of the 2012 corn crop. An early harvest—before the 

August 31 end of the previous marketing year—creates an overlap of supply-and-use 

data between the old and new marketing years that can alter the patterns of corn use 

and ending stocks, with implications for official USDA projections and estimates.

Early harvest and usage of new-crop corn can raise non-feed-and-residual use categories and/or ending stocks in the old marketing year. Feed and residual use of corn is 

the accounting category used to balance corn supply and demand, derived as total 

supply minus all other (non-feed-and-residual) uses minus ending stocks. Thus, any 

increases in non-feed-and-residual uses or ending stocks in the old marketing year 

related to an early harvest of the next year’s corn crop would lower the residual derivation of corn feed and residual use for the old marketing year. To analyze this effect, an 

econometric and statistical model for marketing-year feed and residual use for total 

feed grains is developed. The model augments typical economic explanatory factors 

for feed demand with statistical factors related to the residual nature of this balance 

sheet component. The effect of an early harvest of the corn crop is represented in the 

model by the percent of the corn crop rated mature on August 31, a statistic reported by 

USDA’s National Agricultural Statistics Service (NASS).  Results suggest that for each 

10-percentage-point increase in the August 31 new-corn-crop maturity rating, estimated old-crop feed and residual use of corn falls by almost 120 million bushels.

Keywords: Corn feed and residual, supply-and-demand balance sheet, demand analysis, real corn prices, grain-consuming animal units, corn used in ethanol production, 

corn production, crop maturity rating
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Acknowledgments

The authors thank Joy Harwood and Peter Riley, USDA, Farm Service 

Agency; Patrick Westhoff, University of Missouri; David Stallings, USDA, 

World Agricultural Outlook Board; and Maurice Landes and Linwood 

Hoffman, USDA, Economic Research Service for their many helpful review 

comments on earlier drafts of the report. This report also benefited from input 

from Joseph Prusacki and Daniel Kerestes, USDA, National Agricultural 

Statistics Service; and Gerald Bange and Keith Menzie, USDA, World Agricultural Outlook Board. The authors also thank Priscilla Smith for editorial 

assistance and Cynthia A. Ray for graphics and layout assistance.
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With relatively mild weather this past winter across much of the United 

States, prospects were favorable for the 2012 U.S. corn crop to be planted 

early this year. Planting progress data for corn indicated an advanced pace 

through much of the spring. Figure 1 shows that corn plantings as of midApril and late April 2012 were ahead of the typical pace.

1 As a result, prospects also may be good for an early harvest, with the possibility of a higher 

than typical portion of the 2012 crop being harvested before September 1, the 

start of the official 2012/13 U.S. corn marketing year.

An early harvest of new-crop corn has potential implications for non-feedand-residual usage, ending stocks, and the derivation of feed and residual 

usage of corn for the old marketing year, as well as for available supplies in 

the first quarter of the new marketing year. To understand how these potential 

effects can occur, we first discuss the role of the supply-and-demand balance 

sheet in agricultural commodity market analysis and the sources of information used for its different components.

1Estimates of corn plantings shown in 

figure 1 are based on Prospective Plantings and estimates of planting progress 

for 18 major corn producing States (17 

States in the 1990s). These States represented 92 percent of corn plantings in 

2011. For 2012, this 18-State planting progress aggregate measure may 

understate total corn planting progress 

since several Southern States, with total 

prospective plantings of more than 3 

million acres, are not included.

Introduction
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The supply-and-demand balance sheet is the primary vehicle used by USDA for 

commodity market analysis. It is used to summarize commodity markets historically as well as the Department’s short-term and long-term outlook projections 

(USDA (a) and USDA (b)). It is also used as the basic analytical and reporting 

framework for studies of commodity market effects resulting from alternative 

scenarios for agricultural policies or supply-and-demand prospects.

Table 1 shows the corn supply-and-demand balance sheet for marketing years 

2006/07 through 2010/11. Major supply-and-demand categories are included 

as well as marketing year farm-level corn prices. Supply components of 

the U.S. corn balance sheet are survey-based statistics collected by USDA’s 

National Agricultural Statistics Service (NASS) or statistics reported by 

other official U.S. Government sources. NASS provides data on planted and 

harvested acreage, yields, and production. Imports are based on data from the 

U.S. Department of Commerce. Stocks data are survey-based estimates from 

NASS. The sum of beginning stocks, production, and imports gives total 

supply. Thus, all components of supply are statistically based.

Feed and Residual Usage Balances Corn

Supply and Demand

Table 1

U.S. corn supply-and-demand balance sheet, 2006/07 - 2010/11

Item 2006/07 2007/08 2008/09 2009/10 2010/11

Area (million acres):

Planted acres 78.3 93.5 86.0 86.4 88.2 

Harvested acres 70.6 86.5 78.6 79.5 81.4 

Yields:

Bushels per harvested acre 149.1 150.7 153.9 164.7 152.8 

Supply and use (million bushels):

Beginning stocks 1,967 1,304 1,624 1,673 1,708 

Production 10,531 13,038 12,092 13,092 12,447 

Imports 12 20 14 8 28 

 Supply 12,510 14,362 13,729 14,774 14,182 

Feed & residual 5,540 5,858 5,182 5,125 4,793 

Food, seed, & industrial 3,541 4,442 5,025 5,961 6,428 

 Ethanol and byproducts 2,119 3,049 3,709 4,591 5,021 

 Domestic use 9,081 10,300 10,207 11,086 11,220 

Exports 2,125 2,437 1,849 1,980 1,835 

 Total use 11,207 12,737 12,056 13,066 13,055 

Ending stocks 1,304 1,624 1,673 1,708 1,128 

Prices (dollars per bushel):

Farm price 3.04 4.20 4.06 3.55 5.18 

Note: Marketing year beginning September 1 for corn. 

Source: USDA, Economic Research Service, Feed Grains Database.
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Most of the demand categories also reflect available data sources. Exports are 

based on data from the U.S. Department of Commerce. Seed use is derived 

from acreage data from NASS. Components of food and industrial use (other 

than corn used in ethanol production)—which include uses for production of high fructose corn syrup, glucose and dextrose, starch, beverage and 

manufacturing alcohol, cereals, and other food items—are based on data 

from various Governmental and nongovernmental sources. Corn used in the 

production of ethanol and related feed byproducts is estimated by USDA 

based on ethanol production data reported by the Energy Information Administration of the U.S. Department of Energy.

In the balance sheet, supply minus demand must be equal to the survey-based 

ending stocks estimate reported by NASS. In the corn balance sheet, there is 

no direct measure of feed use.

2 Thus, the category used to obtain the required 

balance is the residually derived feed and residual use of corn. In the balance 

sheet, feed and residual use is derived to equal supply minus all other uses 

minus ending stocks. Implicitly, this derived component of the balance sheet 

includes actual feed use, measurement and estimation errors in other components of the balance sheet, and postharvest crop loss factors such as waste 

and shrinkage that occur throughout the corn marketing channel. To illustrate, 

with recent U.S. corn crops of 12-13 billion bushels, if production estimate 

errors and crop losses combine to represent 1 percent of production, feed and 

residual would change by 120-130 million bushels.

2USDA does not survey for grain 

used in feeding and relies on surveybased production and quarterly stocks 

estimates to indicate grain disappearance. Surveying for feeding would 

require a substantial increase in resources. Such a survey might also prove 

impractical, given the vast array of 

feeding operations that make up the Nation’s swine, beef cattle, dairy, broiler, 

layer, and turkey production sectors.

These operations are diverse and use 

a wide and complex variety of feed 

products in addition to grains. There is 

also a significant amount of feed use of 

grain that occurs outside the conventional livestock, dairy, and poultry 

sectors and includes feeding of horses, 

household pets, and aquaculture, all of 

which present additional challenges to 

any comprehensive survey of grain used 

in feeding.
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The official marketing year for corn starts September 1 and runs through 

August 31 of the following year. An early harvest of the corn crop—before 

the August 31 end of the previous marketing year—creates an overlap of 

supply-and-use data between the old and new marketing years. This overlap 

can affect the residual derivation of corn feed and residual use for the 

previous marketing year in two ways.

3

First, when the harvest of the new crop occurs early (before August 31, the 

end of the previous corn marketing year), some of the new crop may be used 

by August 31, augmenting use at the end of the previous marketing year 

without displacing old-crop usage. If this occurs for uses other than feed and 

residual, estimates for those use components would be increased without 

changing old-crop ending stocks.

4 As a result, the derived feed and residual 

use calculation for that previous marketing year would be lowered.

Second, early use of the new crop in the previous marketing year may 

displace some use of old-crop corn in that same marketing year. If newcrop use displaces some old-crop use, the estimate of old-crop stocks on 

September 1 would be higher than in the absence of this early new-crop 

usage since the displaced corn would be part of ending stocks. This increase 

in year-ending old-crop stocks lowers the derived feed and residual use estimate for the old-crop marketing year in the supply-and-demand balance sheet.

Another potential effect of an early corn harvest is that total available 

supplies of corn in the new marketing year may be less than the sum of 

beginning stocks, new-crop production, and imports because of early usage 

of some of the new-crop production. As a consequence, derived feed and 

residual use for the new-crop marketing year would be increased, particularly 

during the harvest quarter (September-November).

3See the appendix for numerical 

illustrations of these types of effects.

4The NASS estimate of September 1 

corn stocks covers only old-crop corn 

rather than a comingled pool of both 

new- and old-crop corn (see, for example, USDA/NASS, September 2011 

Grain Stocks report).

Potential Effects of an Early Corn Harvest
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An annual econometric and statistical model was developed to investigate 

how an early corn harvest can affect the residually derived feed and residual 

corn use category.

5 Because of the residual nature of the calculation used to 

derive this utilization variable, both economic and statistical factors are used 

in the model as explanatory variables. The economic factors are intended to 

provide measures of effects related to actual feed use, while the statistical 

factors are intended to provide measures of effects related to the residual 

component. The model draws on information and data readily available to 

USDA interagency commodity estimates committees and is typical of models 

used by those committees in their market analysis process.

Model’s Dependent Variable Is Feed and Residual Use 

of Total Feed Grains 

Although corn is the dominant feed grain used in animal feeding, overall 

livestock sector demand for feed also includes feed use of other feed grains.

Thus, the model uses annual data for feed and residual use for total feed 

grains, covering feed and residual use of corn, sorghum, barley, and oats.

6

Data for the different feed grains are converted from units of million bushels 

to metric tons to allow aggregation in common units. This step is needed 

because standard bushels of the different feed grains have different physical 

weights—56 pounds per bushel for corn and sorghum, 48 pounds for barley, 

and 32 pounds for oats.

7 Implications for corn can be drawn from models using 

this aggregate feed demand approach by netting out feed uses for the other feed 

grains and then converting the result back to 56-pound corn bushels.

8

5The analysis does not cover quarterly patterns of feed and residual use 

within a marketing year.

6Annual data for corn and sorghum 

reflect a marketing year that begins 

September 1. Annual data for barley 

and oats are for a marketing year beginning June 1. In the model discussed in 

this report, no adjustment was made 

to account for the different periods 

covered in these marketing years. This 

follows the approach used for the aggregated U.S. feed grains balance sheet 

in USDA’s monthly World Agricultural 

Supply and Demand Estimates report 

(USDA (a)). However, implications are 

similar from an alternative version of 

the model reported here that does adjust 

all feed and residual use data to a common September-August time period.

7For oats, 38-lb bushels are used for 

imports. Implicitly, this means that feed 

and residual use for oats is a blend of 

32-lb bushels and 38-lb bushels. This 

difference is not accounted for here in 

the aggregation of feed and residual 

uses across the different feed grains. Its 

effect on the aggregate series is small, 

on the order of 0.3 million metric tons 

or about 0.2 percent, and its effects on 

the model estimation and implications 

would be negligible.

8While the model could be specified 

for corn feed and residual use directly, 

accounting for the four feed grains 

provides a more complete representation of overall livestock-sector feed 

demand and improves the statistical 

explanatory power for corn feed and 

residual use. On the other hand, wheat 

feed and residual use is not included in 

the model since doing so reduces the 

model’s explanatory power for corn 

feed and residual use. Although wheat 

feed and residual use is somewhat 

larger than that for sorghum, barley, or 

oats, it is much smaller relative to the 

crop’s production, and thus may have a 

larger residual component.

Feed and Residual Use Model
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Economic Factors Affecting Feed and Residual Use 

Three variables are included to represent economic factors affecting actual 

feed use.

Corn prices. The first economic variable is the price of feed. This is 

represented in the model by the real corn price, calculated as the nominal 

marketing-year weighted-average corn price received by farmers divided 

by the consumer price index (CPI). The annual CPI used for this real corn 

price calculation is for the calendar year following the year of harvest of the 

corn crop, chosen because more months of the corn marketing year occur 

in that calendar year. Thus, for example, the CPI for 2011 is used to deflate 

the 2010/11 marketing year corn price. Also, while the CPI data are in units 

of 1982-84 = 100, they are converted to units of 1982-84 = 1.0 so that the 

resulting real corn prices are in similar units to the original nominal prices.

Economic theory suggests that feed use of feed grains would decrease if the 

price of corn rose, implicitly representing a movement up the feed demand 

curve. Thus, the sign on the coefficient of this variable in the model is 

expected to be negative. Figure 2 shows historical data for total feed grains 

feed and residual use and the real corn price. A general negative relationship 

is illustrated.
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Size of the livestock sector (grain-consuming animal units). A second 

economic variable included in the model is a measure of the size of the 

overall livestock sector. An index of grain-consuming animal units (GCAUs) 

has been published by USDA for many years (Allen, Hodges, and Devers, 

1974; Baker, 1998). This index weights animal numbers for different livestock categories by technical factors related to their feed requirements and 

their feed conversion efficiency in a manner that allows a summation across 

the groups. Although this statistic has been criticized at times as a standalone feed demand measure because of its use of weighting factors that do 

not reflect changing feed efficiencies, it still provides a useful overall indicator of feed demand.

The larger the size of the livestock sector, as measured and indicated by a 

larger GCAU, the greater overall feed demand would be, so the sign on the 

coefficient of this variable in the model is expected to be positive. From an 

economic perspective, this would depict a shift of the feed demand curve to 

the right. Figure 3 shows historical data for total feed grains feed and residual 

use and this economic explanatory variable. There is much less variation in 

GCAUs than there is in real corn prices shown in figure 2.
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Availability of competing feeds (distillers’ dried grains). The third 

economic variable included in the model is the amount of corn used in the 

production of ethanol. This variable serves as a proxy for the availability of 

distillers’ dried grains (DDGs) as a competitive feed source to feed grains.

There has been a large and rapid expansion of the ethanol sector in the 

United States over the past decade. Since corn is the primary feedstock used 

for U.S. ethanol production and since most of the expansion has been in 

the dry mill ethanol production process, supplies of the DDGs co-product 

have expanded sharply as well (Hoffman and Baker, 2010). The aggregate 

substitution of DDGs for other feeds in U.S. livestock rations depends on the 

overall share of DDGs production that is used in the United States, the shares 

of DDGs that go to the feeding of different livestock, and the substitution 

of DDGs for corn and other feeds in animal-specific rations (Hoffman and 

Baker, 2011). The variable used here for the model, corn used in the production of ethanol, is intended to represent the net effect of these considerations.

The greater the availability of DDGs, as represented by higher levels of 

corn used in the production of ethanol, the lower the amount of overall feed 

demand for feed grains. Thus, the sign on the coefficient of this variable in 

the model is expected to be negative. From an economic perspective, this 

would depict a shift of the feed demand curve to the left. Figure 4 shows 

historical data for total feed grains feed and residual use and this economic 

explanatory variable. The large expansion of ethanol production over the past 

decade (and the related increase in availability of DDGs) appears to have a 

strong negative relationship to feed grains feed and residual use.
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Statistical Factors Affecting the Estimation

of Feed and Residual Use

Two variables are included in the model to represent statistical issues that can 

have effects due to the residual nature of the derivation of feed and residual 

use.

Size of the corn crop. Corn production is included in the model to represent 

the size of the crop.

9 Its inclusion is based on the hypothesis that the larger 

the size of the crop, the larger the potential for crop shrinkage and losses and 

for measurement and estimation errors in other components of the supplyand-demand balance sheet.

10 

Since potential losses and errors would be positively correlated with the size 

of the crop, the residual component of the feed and residual measure would 

also be positively correlated with this variable. Thus, the sign on the coefficient of corn production would be expected to be positive. Figure 5 shows 

historical data for total feed grains feed and residual use and this potential 

explanatory variable for the statistical “residual” component. A general positive relationship is illustrated.

9Typically, a supply variable would 

not be included in a demand equation 

because of technical identification issues. However, here the crop production variable is intended to capture 

statistical aspects of the residual component of the feed and residual variable 

rather than economic aspects of feed 

demand.

10Some crop shrinkage can result 

from differences in the quality of the 

crop due to moisture content and test 

weights that affect estimates of crop 

production. This factor would be 

independent of the size of the crop and, 

thus, would not be represented in the 

model.
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Early harvest of following year’s corn crop. As discussed earlier, the 

larger the early harvest of the following year’s corn crop, the higher the 

potential for early new-crop usage and a larger year-ending old-crop stocks 

estimate. As a consequence, early new-crop harvesting can result in a smaller 

feed and residual calculation for the old-crop marketing year.

Ideally, to represent the effects of an early harvested crop, one would use data 

for the amount of the crop harvested prior to September 1. However, while 

such data is available for some years for some States, this information is 

readily available only on an irregular basis over the past 20 years. As a proxy 

for that information, the model uses the percent of the corn crop that is rated 

“mature” by August 31, since this would be a precondition for the crop to be 

harvested. This data is reported by NASS in the weekly Crop Progress and 

is repeated in the joint U.S. Department of Commerce and USDA Weekly 

Weather and Crop Bulletin.

11 Because the early harvest of a corn crop is 

hypothesized to reduce the estimate of the previous year’s feed and residual 

use, a time period lead of 1 year (t+1) applies to the corn maturity variable.

Figure 6 shows historical data for this corn maturity variable with feed grains 

feed and residual use since 1990, suggesting a rough negative relationship.

11This data is typically first reported 

for late August or early September.

Data were interpolated between weekly 

reports to approximate a corn crop 

maturity rating for August 31. For years 

that the first maturity ratings were not 

available until September, data were 

extrapolated back to August 31.
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The model for feed grain feed and residual use discussed here was estimated 

using annual marketing-year data for the period 1990/91 through 2010/11.

The ordinary least squares (OLS) method was the model estimation procedure. Results are shown in table 2. Overall, the model performs very well, 

with over 95 percent of the variation of feed grain feed and residual use 

explained. Each of the estimated coefficients on the explanatory variables has 

the expected sign and is significant at the 1 percent level.

Figure 7 shows a plot over the estimation period of the actual observations 

for feed grain feed and residual use as well as the model estimates. Also 

shown in the figure are two beyond-sample actual- and model-observations 

for 2011/12 and 2012/13. These beyond-sample period estimates are based 

on projected independent variables from USDA’s May 2012 World Agricultural Supply and Demand Estimates (WASDE) and Feed Outlook reports.

Also, corn crop maturity in these beyond-sample estimates was assumed to 

be at the average over the model estimation period.

Model Implications for Corn Feed and Residual Use

Of primary interest are the implications of this model for feed and residual 

use of corn. To obtain these results, feed and residual use for sorghum, barley, 

and oats are subtracted from the model estimates for total feed grains feed 

and residual use. The result for corn feed and residual use is then converted 

from units of million metric tons to million bushels.

12 Figure 8 shows the 

resulting model implications for corn feed and residual use along with the 

actual data for that series. These model implications explain over 96 percent 

of the variation of corn feed and residual use over the 1990/91-2010/11 estimation period. Again, beyond sample estimates are based on projected independent variables from the above cited sources and assume the average for 

crop maturity on August 31 over the model estimation period.

12A metric ton is 2,204.622 pounds.

A bushel of corn weighs 56 pounds.

Thus, to convert from metric tons to 

corn bushels, one multiplies by the 

ratio of these two factors, or 39.36825 

bushels per metric ton.

Model Results and Selected Model 

Properties

Table 2

Econometric regression results: Feed grains feed and residual use model 

Intercept

Real corn 

price GCAU

Corn used 

in ethanol 

production

Corn 

production

Corn crop (t+1), 

percent mature, 

August 31

Coefficient 58.710 -10.771 0.838 -0.00810 0.00480 -0.303 

Standard error of coefficient 2.902 0.262 0.00115 0.00077 0.101 

t-statistic -3.712 3.201 -7.034 6.232 -3.006 

R-squared 0.953 Estimation period 1990/91 - 2010/11

Standard error 2.601 Number of observations 21 

F-statistic 61.1 Degrees of freedom 15 
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Other important model implications for corn feed and residual use include:

Economic factors related to feed demand

•	The implicit corn feed and residual use change for a 1-percent change in

the real corn price, evaluated at 2010/11 prices is -9.8 million bushels.

This result implies an own-price feed demand elasticity of -0.20.

•	The implicit corn feed and residual use change for a 1-unit increase in

GCAUs is +33.0 million bushels, derived as the GCAU coefficient of 

0.838 times the bushels-per-metric-ton conversion factor of 39.36825.

13

For 2010/11, this implies a change of about 0.64 percent corresponding 

to a 1-percent change in GCAUs. This inelastic result, where a 1-percent 

increase in GCAUs results in less than a 1-percent increase in feed use, 

partly reflects improvements in feed efficiency, including a growing share 

of broilers (the most efficient feed converter) in the mix of animals fed.

•	The implicit corn feed and residual use change for a 100-million-bushel

increase in corn used for ethanol is -31.9 million bushels. This result 

suggests an aggregate substitution of DDGs for corn in livestock rations 

somewhat larger than 1 for 1, consistent with some of the alternatives 

discussed in Hoffman and Baker (2011).

Statistical factors related to residual component

•	The implicit corn feed and residual use change for a 100-million-bushel

increase in corn production is +18.9 million bushels, an estimate of 

the marginal effect of larger production on postharvest crop losses and 

measurement errors across all other components of the corn supply-anddemand balance sheet. The relatively large size of this impact could also 

suggest that an increase in corn production results in higher actual feed use 

beyond what is captured by the economic factors included in the model.

•	The implicit old-crop corn feed and residual use change for a

10-percentage-point increase in the new-corn crop rated mature by 

August 31 is -119.4 million bushels.

Model projections for corn feed and residual use

The model can be used to make projections for years beyond its estimation 

period. For the illustrations here, model projections are based on independent variables from the May 2012 WASDE and Feed Outlook reports. Also, 

the corn crop maturity rating (for the following year’s crop) is assumed at the 

1990-2010 average.

•	Based on these assumptions, the model projection for 2011/12 corn feed and

residual use is 4,717 million bushels.

•	With these assumptions, the model projection for 2012/13 corn feed and

residual use is 5,432 million bushels.

13The GCAU coefficient of 0.838 

provides this impact in million metric 

tons. Multiplying by 39.36825 converts 

this result to units of million bushels.
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Other Modeling Considerations

Two alternative specifications of the annual model discussed in this report 

were used to test for effects of an early harvest on new-crop feed and 

residual use—no statistically significant effect was indicated. Since any such 

effect would be expected to be mostly in the harvest quarter (SeptemberNovember), a similar model was estimated for feed and residual use in the 

first quarter of the new marketing year. Results from this model suggest a 

marginally statistically significant increase of about 33 million bushels (standard error of 21 million bushels) in first quarter feed and residual use of corn 

for a 10-percentage-point higher new-crop maturity rating on August 31.

This is a relatively small impact compared with the estimated effects on 

annual feed and residual use in the previous marketing year corresponding 

to the same crop maturity change. One possible reason for this smaller result 

may be that residual effects may show up more readily at the end of the crop 

year, when total market supplies are seasonally low, than in the first quarter 

of the new crop year when the new-crop production dominates supplies.
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As reported above, the estimated model implies a corn feed and residual use level 

of 4,717 million bushels for the soon-to-be completed 2011/12 corn marketing 

year. This model projection assumed the percent of the corn crop rated mature 

on August 31 would be equal to the average over the model estimation period, 

which was 12.5 percent. Also reported above, for each 10 percentage point 

increase in the new-corn-crop maturity rating, the model estimates a reduction of 

119.4 million bushels in the old corn crop’s feed and residual use.

Using these results, model projections can be derived for 2011/12 corn feed 

and residual use for various levels of the 2012 corn crop maturity rating.

Table 3 shows implications of different 2012 corn crop maturity ratings from 

10 percent to 30 percent. For example, the model projection for 2011/12 corn 

feed and residual use is lowered to 4,568 million bushels if the 2012 corn 

crop rated mature by August 31 is at the sample maximum of 25 percent 

rather than the average of 12.5 percent.

Implications of an Early 2012 Corn Harvest

Table 3

2011/12 model projections for corn feed and residual use for different shares 

of the 2012 corn crop rated mature by August 31

2012 corn crop maturity rating, August 31Model projection for 

2011/12 corn feed and residual use

Difference from model projection based 

on sample average maturity rating

Percent ---------------------- Million bushels ----------------------

10 4,747 30 

11 4,735 18 

12 4,723 6 

12.5, sample average 4,717 0

13 4,711 -6 

14 4,699 -18 

15 4,687 -30 

16 4,675 -42 

17 4,663 -54 

18 4,651 -66 

19 4,639 -78 

20 4,627 -90 

21 4,615 -102 

22 4,604 -113 

23 4,592 -125 

24 4,580 -137 

25, sample maximum 4,568 -149 

26 4,556 -161 

27 4,544 -173 

28 4,532 -185 

29 4,520 -197 

30 4,508 -209 

Based on projections for other model variables from USDA’s May 2012 World Agricultural Supply and Demand Estimates and Feed Outlook reports.
18

Implications of an Early Corn Crop Harvest for Feed and Residual Use Estimates / FDS-12f-01

Economic Research Service/USDA

The 2012 U.S. corn crop has the potential to have a larger than typical 

amount harvested early, before the August 31 end of the 2011/12 marketing 

year. To the extent that some early-harvested, new-crop corn is used before 

the start of September, some old-crop corn usage may be displaced. If so, 

this could raise estimated old-crop ending stocks for the 2011/12 marketing 

year and result in a correspondingly lower derived calculation for feed and 

residual use. Further, even if early new-crop usage does not displace old-crop 

usage, it may augment use at the end of the 2011/12 marketing year. If this 

additional use occurs for uses other than feed and residual, again the derived 

2011/12 feed and residual use calculation will be lowered.

The model discussed in this report includes both economic factors and statistical measurement considerations underlying historical feed and residual use.

The model provides a framework for projecting effects on derived 2011/12 

feed and residual use for different economic conditions and for different 

assumptions regarding the amount of the early-harvested 2012 corn crop.

Another implication of an early harvest is that available supplies of corn in 

the new marketing year may be less than the sum of beginning stocks, newcrop production, and imports because of early usage of some of the newcrop production.

Conclusions
19

Implications of an Early Corn Crop Harvest for Feed and Residual Use Estimates / FDS-12f-01 

Economic Research Service/USDA

Allen, George C., Earl F. Hodges, and Margaret Devers. 1974. LivestockFeed Relationships—National and State, Statistical Bulletin 530, U.S.

Department of Agriculture, Economic Research Service, June.

Baker, Allen J. 1998. “Estimating Feed Use: Background and Issues,” 

Feed Yearbook, FDS-1998, U.S. Department of Agriculture, Economic 

Research Service, April.

Hoffman, Linwood A., and Allen Baker. 2010. Market Issues and Prospects for U.S. Distillers’ Grains Supply, Use, and Price Relationships, 

FDS-10K-01, U.S. Department of Agriculture, Economic Research 

Service, December.

Hoffman, Linwood A., and Allen Baker. 2011. Estimating the Substitution of 

Distillers’ Grains for Corn and Soybean Meal in the U.S. Feed Complex, 

FDS-11-I-01, U.S. Department of Agriculture, Economic Research 

Service, October.

U.S. Department of Agriculture (a). World Agricultural Supply and Demand 

Estimates, WASDE series, monthly.

U.S. Department of Agriculture (b). 2012. USDA Agricultural Projections to 

2021, Long-term Projections Report, OCE-2012-1, February.

U.S. Department of Agriculture, Economic Research Service Feed Grains 

Database, available at http://www.ers.usda.gov/data-products/feed-grainsdatabase.aspx.

U.S. Department of Agriculture, Economic Research Service. 2012. Feed 

Outlook, FDS-12e, May.

U.S. Department of Agriculture, National Agricultural Statistics Service.

Crop Progress, available at http://usda.mannlib.cornell.edu/MannUsda/

viewDocumentInfo.do?documentID=1048/.

U.S. Department of Agriculture, National Agricultural Statistics Service.

2011. Grain Stocks, September 2011, available at

http://usda01.library.cornell.edu/usda/nass/GraiStoc//2010s/2011/

GraiStoc-09-30-2011.pdf/.

U.S. Department of Agriculture, National Agricultural Statistics Service.

Quick Stats, available at http://quickstats.nass.usda.gov/ .

U.S. Department of Commerce and U.S. Department of Agriculture. Weekly 

Weather and Crop Bulletin, available at http://usda.mannlib.cornell.edu/

MannUsda/viewDocumentInfo.do?documentID=1393/.

U.S. Department of Labor, Bureau of Labor Statistics. Consumer Price Index 

Database, available at http://www.bls.gov/data/.

Westcott, Paul. 2007. Ethanol Expansion in the United States: How Will the 

Agricultural Sector Adjust?, FDS-07D-01, U.S. Department of Agriculture, Economic Research Service, May.

References
20

Implications of an Early Corn Crop Harvest for Feed and Residual Use Estimates / FDS-12f-01

Economic Research Service/USDA

Early new-crop usage results when some of the next marketing year’s crop 

is harvested and consumed before the end of the current marketing year.

Although some early usage likely occurs every year, as long as that volume of 

consumption is relatively consistent from year to year, effects tend to be offsetting across marketing years in the supply-and-demand balance sheet. However, 

if the pattern of early harvesting and usage changes between years, the balance 

sheet for both the current and following marketing years can be affected.

Appendix table 1 provides a simplified supply-and-demand balance sheet for 

a hypothetical commodity to illustrate the impacts resulting from early new 

crop usage. This balance sheet assumes a base scenario where stocks, production, and use are the same in both the current marketing year (yeart

, shown 

as items 1-7), and the next marketing year (yeart+1, shown as items 8-14).

For simplification, the base scenario assumes no early harvest and use of the 

next marketing year’s crop in the current marketing year. Different assumptions regarding early harvest and use and the associated effects on the balance 

sheet are then illustrated in the other scenarios.

Scenario 1 assumes 10 units of the next year’s (yeart+1) production is 

consumed in the current year (yeart) as an additional reported use (use other 

than for feed and residual), with no displacement of use of current-year 

supplies, thereby raising other uses to 510 units. Since no displacement of 

current-year supplies occurs, old-crop ending stocks as surveyed by NASS 

remain unchanged at 100 units. Thus, derived feed and residual use declines 

in the current year to offset the increase in other uses. Supplies in the next 

year now include 10 units of production that have already been used in the 

previous year. These already-used units will not be part of reported stocks 

at the end of the second year, so ending stocks are reduced to 90 units. With 

no changes in other uses in the second year, calculated feed and residual use 

increases by 10 units.

Scenario 2 also assumes 10 units of the next year’s (yeart+1) production is 

consumed in the current year (yeart). Here the early usage is assumed to 

displace 10 units of the current year’s supplies from use, leaving other uses 

unchanged at 500 units. The displaced supplies become part of the NASSsurveyed, old-crop ending stocks. With ending stocks thus raised 10 units to 

110, calculated feed and residual use declines 10 units in the current year.

As in scenario 1, 10 units of production for the next year have already been 

consumed in the preceding year and will not be part of reported stocks at the 

end of the second year, so ending stocks are 10 units lower than beginning 

stocks. Thus, calculated feed and residual use is again 10 units higher in the 

second year.

Each of these scenarios demonstrates that changes in the pattern of early 

usage have multi-year impacts on the supply-and-demand balance sheet.

Both situations are likely to occur when there is an early harvest of a crop, 

so a combination of effects such as depicted in scenarios 1 and 2 would be 

Appendix—Impacts of Early New-Crop 

Usage on a Supply-and-Demand

Balance Sheet
21

Implications of an Early Corn Crop Harvest for Feed and Residual Use Estimates / FDS-12f-01 

Economic Research Service/USDA

reflected in commodity balance sheets. By holding production levels and 

other uses (reported uses for non-feed-and-residual-use categories) in the 

second year the same as in the base scenario, implications for ending stocks 

and the derived residual use category can be clearly shown.

In the real world, with the supply-and-use elements of the balance sheet 

affected by numerous additional factors, separating these early-harvest effects 

into measurable impacts is not possible. What is evident, however, is that an 

increase in early harvest and usage of a new crop (1) affects the derived estimates of old-crop feed and residual; and (2) reduces actual available supplies 

in the following marketing year from those calculated based on reported 

data, thereby implying an offsetting increase in that year’s derived feed and 

residual use in the supply-and-demand balance sheet.

Appendix table 1

Scenarios for early new crop usage in a hypothetical commodity supply-and-demand balance sheet

Item 

no.

Simplified balance sheet 

categories Source Base scenario

New-crop usage scenarios

Scenario 11 Scenario 22

Yeart

1 Beginning stocks Reported 100 100 100

2 Production Reported 900 900 900

3 Total supply3 (1 + 2) 1,000 1,000 1,000

4 Feed & residual use (3 - 7 - 5) 400 390 390

5 Other uses Reported 500 510 500

6 Total use (4 + 5) 900 900 890

7 Ending stocks Reported 100 100 110

Yeart+1

8 Beginning stocks Reported 100 100 110

9 Production Reported 900 900 900

10 Total supply3 (8 + 9) 1,000 1,000 1,010

11 Feed & residual use (10 - 14 - 12) 400 410 410

12 Other uses Reported 500 500 500

13 Total use (11 + 12) 900 910 910

14 Ending stocks Reported 100 90 100

1Scenario 1 assumes early usage of yeart+1 production raises reported other uses in yeart

 by 10 units. 2Scenario 2 assumes early usage of yeart+1 production displaces usage of yeart

 supplies, raising ending stocks in yeart by 10 units. 3Assumes no imports.