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Oregon -- Population -- Statistics, Demographic surveys -- Oregon, Population forecasting -- Oregon -- Union County


Union County’s total population has grown slowly since 2000, with an average annual growth rate of half percent between 2000 and 2010 (Figure 1). However, some of its sub-areas experienced more rapid population growth during the 2000s. Summerville posted the highest average annual growth rate of 1.4 percent, and Imbler and Union were close behind with average annual growth rates of about 1.2 percent each.

Union County’s positive population growth in the 2000s was the combined result of a consistent natural increase and a net in-migration. The larger number of births relative to deaths has led to a natural increase (more births than deaths) in every year from 2000 to 2015 (Figure 12). While net in-migration fluctuated dramatically during the early years of the last decade, the number of in-migrants has been slightly more stable during recent years, accounting for the majority of Union County’s population increase.

Total population in Union County as a whole as well as within some of its sub-areas will likely grow at a slightly faster pace in the nearer-term (2016 to 2035) compared to the longer-term (Figure 1). The tapering of growth rates is largely driven by an aging population—a demographic trend which is expected to contribute to natural decrease (more deaths than births). As natural decrease occurs, population growth will become increasingly reliant on net in-migration.

Steady increase in net in-migration is expected to offset the growing natural decrease, leading to relatively steady population growth over the forecast period. However, an aging population is expected to not only lead to an increase in deaths, but a smaller proportion of women in their childbearing years will likely result in a long-term stabilization in the number of births.


This report is published by the Population Research Center at Portland State University, and is a product of the Oregon Population Forecast Program.

The introductory presentation, preliminary forecast presentation, and Union County final forecast tables are attached to this document as supplemental files.

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R2_Union_201509-10.pdf (1233 kB)
Introductory presentation

UnionCountyPreliminaryPresentation_rev.pdf (691 kB)
Preliminary forecast presentation

Union_County_Final_Forecast_Tables.ods (51 kB)
Final forecast tables