Sun Corridor Projections

This step will develop three sets of projection scenarios for the "Sun Corridor" region that includes Maricopa, Pinal and Pima Counties. The study of this single three-county area includes three major parts: (1) Demographics, (2) Economics, and (3) Projection Scenarios.


This white paper reviews historic trends for total population, vital rates, net natural increase, domestic immigration, and foreign immigration. As the three-county study will make separate projections for Hispanic and non-Hispanic populations, demographic trends for those are shown separately. This white paper also examines previous projections for Pinal County, as well as comments gained through expert interviews. The paper concludes with scenario assumptions for the most important demographic influences: immigration, working-age domestic migration, retirement-age domestic migration, and net natural increase. Finally, other factors likely to influence growth in the three-county region are addressed — economic development, real estate prices, urban disamenities, resource limitations, and climate change. Download the paper here.


This white paper examines the long term economic forces that could impact the economic development of the three county megapolitan region that includes Pinal, Maricopa and Pima Counties. First, it discusses the industry mix and basic industries in the region. Second, it reviews target industries previously identified by a number of economic development organizations and recommends a set of target industries for each county in the megapolitan region. Third, it summarizes the results of economic interviews with 22 economic and planning experts from around Arizona. Fourth, it discusses the lessons learned from a case study that compares the population and economic development growth trajectories in Pinal County and Riverside County, California. Download the paper here.

Sun Corridor Model Specifications

A description of the overall structure of the Sun Corridor projections model can be downloaded here, and a list of each equation in the model can be downloaded here. The projections model of the Sun Corridor is a regression model that depends, in part but importantly, upon projections for the United States. The June 2008 scenarios of Global Insight are being used for national projections. A list of all input variables to the model can be downloaded here. The Sun Corridor model will project a number of economic and demographic variables. These can be downloaded here.

Sun Corridor Projection Scenarios

The projection scenarios were developed using a combined cohort-survival model for natural increase, and a regression model for jobs, which then influence net migration. Specific assumptions are included in each of the three projection scenarios — most likely, most optimistic, and most pessimistic. A workshop on the Sun Corridor projection scenarios was held on January 8, 2009. The presentation made at that workshop can be downloaded here. A white paper presenting the projection scenarios and assumptions underlying each has been developed. Download the paper here.

To contact us:

Central Arizona Association of Governments
2066 W. Apache Trail, Ste. 110 Apache Junction, Arizona 85220
(520) 827-0209
Jack Tomasik, Planning Director