Methodology Behind the Quarterly Food-at-Home Price Database
by Jessica E. Todd
, Lisa Mancino
, Ephraim Leibtag
, and Christina Tripodo
Technical Bulletin No. (TB-1926) 43 pp, April 2010
Food prices are crucial for economic modeling of consumer food
choice and dietary patterns. Variations in living costs and other
market conditions across the United States imply that analyses
using national-level food prices may not accurately capture the
effects of food prices on consumer behavior or well-being.
Measuring local food prices may better indicate the effect of
prices on food choices. Since prices are also likely to fluctuate
across seasons, particularly for perishable goods such as fruits
and vegetables, quarterly prices are preferred to an annual
estimate when modeling food choices.
What Is the Issue?
Despite the fact that food prices are likely to vary across the
country, a dataset that provides a consistent measure of
market-level food prices does not exist. This lack of price data
makes it difficult to study the effects that food prices have on
consumer choices and diet/health outcomes, such as the potential
impact of policies that would alter the relative cost of
foods-possibly through taxes or subsidies-to encourage healthier
What Is the Contribution?
The Quarterly Food-at-Home Price Database (QFAHPD) was developed
to fill the gap in available food price data and to support
research on the economic determinants of diet quality and health
outcomes. The QFAHPD contains regional and market-level quarterly
prices for 52 separate food groups between 1999 and 2006 for 30
market groups (for 1999 to 2001) and 35 market groups (for 2002 to
2006) that cover all 48 contiguous States. The food categories were
created to correspond with the U.S. Department of Health and Human
Services and U.S. Department of Agriculture's 2005 Dietary
Guidelines, as well as to capture price premiums for convenience
and processing. Prices are presented in dollars per 100 grams of
food as purchased. The QFAHPD demonstrates that food prices vary
widely across geographic areas.
How Was the Study Conducted?
We used data from the 1999-2006 Nielsen Homescan panels.
Information on household-level purchases of both UPC (Universal
Product Code)-coded and random-weight food items was aggregated to
estimate household-level quarterly prices for 52 food groups. The
household-level prices were then aggregated to estimate quarterly