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


Different parts of the county experience differing growth patterns. Local trends within the UGBs and the area outside them collectively influence population growth rates for the county as a whole.

Clackamas County’s total population has grown steadily since 2000, with an average annual growth rate of 1.1 percent between 2000 and 2010 (Figure 1). However, some of the county’s sub-areas outside of Clackamas County’s Metro boundary experienced more rapid population growth during the 2000s. Sandy and Molalla posted the highest average annual growth rates at 5.6 and 3.8 percent, respectively, during the 2000 to 2010 period.

Clackamas County’s positive population growth in the 2000s was the direct result of substantial net in-migration. Meanwhile, an aging population not only led to an increase in deaths but also resulted in a smaller proportion of women in their childbearing years. This, along with more women choosing to have fewer children and having them at older ages has led to fewer births in recent years. The larger number of births relative to deaths caused a natural increase (more births than deaths) in every year from 2000 to 2015. Net in-migration outweighed natural increase during the early and middle years of the 2000s, though the gap between these two numbers has narrowed more recently. In more recent years (2013 to 2015) net in-migration has risen—bringing with it population growth (Figure 12).

Total population in Clackamas County and its sub-areas outside of Clackamas County’s Metro boundary will likely grow at a faster pace in the near-term (2017 to 2035) compared to the long-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.

Even so, Clackamas County’s total population is forecast to increase by more than 107,000 over the next 18 years (2017-2035) and by more than 267,900 over the entire 50 year forecast period (2017-2067). Sub-areas that experienced rapid population growth in the 2000s are generally expected to post strong population growth during the forecast period.


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 Clackamas County final forecast tables are attached to this document as supplemental files.

Persistent Identifier

Introductory presentation Clackamas.pdf (2096 kB)
Introductory presentation

clackamas prelim presentation.pdf (1685 kB)
Preliminary presentation

Clackamas_County_Final_Forecast_Tables.xlsx (132 kB)