Projections Methodology

The University of New Mexico Institute for Geospatial and Population Studies (IGPS) releases periodic July 1 population projections for New Mexico and its 33 counties. These projections are used by several state agencies and private entities for research and planning purposes.

IGPS uses a standard cohort component method based on the demographic balancing equation:

Popt = Popt-1+ Births – Deaths + Net Migration

These 2020-2040 five-year interval projections begin with IGPS population estimates. From this, the number of expected deaths is subtracted from the population using life tables calculated from the New Mexico Department of Health. Next, the number of expected births for the female population ages 15-44 is calculated using fertility data from the New Mexico Department of Health. Finally, net migration is calculated based on recent historical trends. This was not straightforward for the 2020-2040 estimates, because of large in-migration between 2000 and 2010 and because of large out-migration between 2010 and 2015. Neither of these trends is expected to soon return or continue. Therefore, migration was roughly calculated as half the net migration observed between 2000 and 2010.

This process is completed for each county and then controlled to a statewide projection total.