Oregon grew by just under 21,000 people in the past year, and Jackson County added just 435.

Oregon grew by just under 21,000 people in the past year, and Jackson County added just 435.

Preliminary population estimates by Portland State University shows that Oregon had 3,844,195 people in 2010, up from 3,823,465 last year.

The increase is only 0.5 percent, marking the fourth straight year of slowing population growth for Oregon, and the slowest growth since the 1980s.

The trend is evident in Jackson County as well. The county's population grew by 435, or .4 percent, to 207,745. Medford's population as of July 1 was 77,485; Ashland's was 21,460.

Growth is the difference between the number of births and deaths, and the number of people moving in or out of the state, called net migration.

Officials said this year there was a decrease in the number of births combined with a slight increase in the number of deaths. Net migration also accounted for a smaller percentage of the overall population growth.

— Wire and staff reports