TRPC develops updated population and employment forecasts every three to five years.  These forecasts are used for transportation, sewer, water, land use, school, and other local governmental planning purposes.  They are also used by the private sector for business planning.  TRPC has been preparing these forecasts periodically since the late 1960s.

The previous countywide forecast was adopted on July 13, 2012. Population distributions to small areas such as cities, towns, tribes, school districts, etc. were adopted on July 10, 2015. Employment allocations were adopted on July 10, 2015.