REGIONS: Regional Population Shares
It is no surprise that Oregon's three most populous counties, in the Portland Metropolitan Area, are home to the largest share of the state's population (currently estimated at 43.5 percent of the state total). What people may not realize is that the share has not changed much since 1910, and currently it is about the same as it was in 1930.
The next most populous region depicted in the chart is the Willamette Valley. At 27 percent of the state total, its share has remained relatively stable since 1970.
The South Coast combined with the inland valleys of Southwest Oregon has accounted for at least one of every eight Oregon residents since 1950.
Central Oregon is the region whose share has increased the most over the past several decades, from 2.3 percent in 1970 to 5.3 percent in 2015.
The other four regions have had declining shares of state population; the Columbia Basin and Northeast Oregon had peak shares in 1900, and North/North Coast and South/Southeast peaked in 1940. However, total population in each of these regions has grown significantly since their shares peaked, and they have continued to grow in the 21st Century.