Information that used to be available only once every ten years will soon be available each year from the Census Bureau. This site has demographic and income data for several pilot counties across the country, including Multnomah County in Oregon.
Produces population estimates for Oregon's counties and incorporated cities and conducts research into the causes and consequences of demographic change.
The Oregon Population Survey is conducted every two years, and gives insight into the state of the population and the opinion of Oregonians on a variety of issues. Download the results of the 2000 population survey here.
The Census Bureau is one of the most comprehesive sources of information about the U.S. population and economy.