Estimates Methodology Statement

The University of New Mexico Institute for Geospatial and Population Studies Department (IGPS) releases annual July 1 population estimates for New Mexico and its 33 counties. These estimates are used for research, planning, revenue and resource distribution, as denominators in epidemiological rates, and as input data for population projections.

For state and county household population totals, IGPS uses three methodologies that are averaged together to reduce the degree of error any one method may introduce.

IGPS uses a cohort component method that tracks births and deaths with data available from the New Mexico Department of Health, and tracks migration using data from the Internal Revenue Service and from Medicare Enrollment figures.

IGPS also uses a housing-unit method that tracks the change in residential housing units (e.g., new construction and demolitions) for all permit-issuing jurisdictions in the state. Data on occupancy rates and average number of persons per household are obtained from the decennial census and from the American Community Survey.

IGPS's third method is a ratio-correlation that uses three indicators of population change: school enrollment data from the New Mexico Public Education Department, voter registration figures from the New Mexico Secretary of State’s Office and driver’s license data from the Motor Vehicle Division (these data are not public).

To track changes of populations living in group quarters, IGPS conducts an annual group quarters survey of larger detention centers, college dormitories and nursing homes throughout the state. Data on populations living on military installation group quarters are obtained from the US Census Bureau and the Defense Manpower Data Center.

IGPS also generates small-area population estimates that include detailed characteristics (age, sex, race, and ethnicity) for the New Mexico Department of Health. Those data are available from our partners at the New Mexico Department of Health.