Definitions: The Healthy Food Financing Initiative (HFFI) Working Group defines a food desert as a low-income census tract where a substantial number or share of residents has low access to a supermarket or large grocery store. To qualify as low-income, census tracts must meet the Treasury Department's New Markets Tax Credit (NMTC) program eligibility criteria. Furthermore, to qualify as a food desert tract, at least 33 percent of the tract's population or a minimum of 500 people in the tract must have low access to a supermarket or large grocery store.
The NMTC program defines a low-income census tract as: any census tract
where (1) the poverty rate for that tract is at least 20 percent, or (2)
for tracts not located within a metropolitan area, the median family
income for the tract does not exceed 80 percent of statewide median
family income; or for tracts located within a metropolitan area, the
median family income for the tract does not exceed 80 percent of the
greater of statewide median family income or the metropolitan area
median family income.
Low access to a healthy food retail outlet is defined as more than 1
mile from a supermarket or large grocery store in urban areas and as
more than 10 miles from a supermarket or large grocery store in rural
areas. The distance to supermarkets and large grocery stores is measured
by the distance between the geographic center of the 1-km square grid
that contains information on the population (number of people and other
characteristics) and the nearest supermarket or large grocery store.
Once the distance to the nearest supermarket or large grocery store is
calculated for each grid cell, the number of people or housing units
more than one mile from a supermarket or large grocery store in urban
tracts (or 10 miles for rural census tracts) is aggregated to the census
tract level. (A census tract is considered rural if the centroid of
that tract is located in an area with a population of less than 2,500,
and all other tracts are considered urban tracts.) If the aggregate
number of people in the census tract with low access is at least 500 or
the percentage of people in the census tract with low access is at least
33 percent, then the census tract is considered a food desert.
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Data Source: U.S. Department of Agriculture, Economic Research Institute
http://www.ers.usda.gov/data/fooddesert/index.htm
The data used for these calculations come from a variety of sources with different collection dates. The analysis cannot be dated with precision.
Footnotes:
Children living in a food-insecure household not located in one of the Census Tracts as defined above, is not counted in the county total.
"0" children in a county means that no Census Tract met the criteria for a food desert in that county and therefore no children were counted.