The following map shows the percentage changes in population in Washington state counties from 1980 to 2000, and is based on U.S. Census Bureau data:
Population growth is comprised of two major components — natural increase and net migration. In the early 1990s, the poor economic climate in California resulted in over 400,000 persons migrating out of state. Many of these people moved to Washington state, which accounts for a large spike in population growth during the 1990s, as shown in the following chart:
For more information on Washington state population statistics, see Population in Washington Trends.