The Census’s Population Estimates Program produces estimates of the population of the United States. The latest US Decennial Census population figures are used as a base, and population change is estimated by modeling estimated births, deaths, and migration. Population Estimates are released annually.

Lightcast uses Population Estimates nearly unchanged in the years for which they are available as the basis for demographics counts for the nation, states, and counties.

To calculate ZIP-level data, we use tract-level population based on Census Population Estimates. The Department of Housing and Urban Development publishes a mapping between tract and ZIP codes which is utilized to create ZIP code estimates.