OLYMPIA — While Washington state’s population growth rate is increasing, Kitsap County numbers have declined, according to annual estimates prepared by the Office of Financial Management.

The report shows that the state’s population increased by 64,600 between 2012 and 2013, to 6,882,400. A near 1 percent gain, it is the largest since 2010.

For Kitsap County, the report estimates about 500 people less than 2012 estimates, from 254,500 to 254,000. But in Port Orchard, the estimates show an increase of 90 people — from 11,780 in 2012 to 12,870 for 2013.

Poulsbo and Bainbridge Island estimates are up, while Bremerton is down. The estimate for county’s largest city for 2013 is 37,850, down from the 39,650 in 2012.

The state’s higher growth rate was driven mainly by migration. This year, net migration (26,800) accounted for 41 percent of the state’s population growth. In 2011 and 2012, net migration as a percentage of total population growth was 13 percent and 24 percent, respectively.

Over the past decade, net migration averaged 45,000 persons per year, accounting for 54 percent of total population growth. Although current migration is lower than the prior decade’s average, it is more than twice as high as last year, suggesting that a population rebound may be starting to take hold after several years of slow growth.

This year’s growth is concentrated in large metropolitan counties. Seventy-three percent of the growth occurred in the state’s five largest counties: Clark, King, Pierce, Snohomish and Spokane. In 2012, these counties accounted for about 65 percent of total population growth. King County accounted for the largest share of state growth this year, almost 39 percent. The strength of the economic recovery in these metropolitan counties is driving the increase in migration.

However, nonmetropolitan counties experienced a decrease in net migration from last year, declining from about 3,600 migrants in 2012 to about 1,600 in 2013. Consequently, the share of state population growth attributed to nonmetropolitan counties declined from nearly 10 percent last year to about 4 percent this year.

The April 1, 2013, population estimate for Washington’s incorporated cities and towns is 4,432,700. This represents an increase of 53,500 people. Unlike last year, population growth in incorporated areas is predominately associated with natural increase and net migration, instead of annexation activity.

The top 10 cities for population growth, in descending order, are Seattle, Bellevue, Pasco, Auburn, Renton, Kent, Spokane, Vancouver, Richland and Kennewick.

Housing growth also accelerated in 2013. The state added 23,300 housing units, an increase of 4,600 units, or 24 percent, as compared to 2012. Almost 68 percent of all new housing is located in the five largest metropolitan counties, up from 61 percent in 2012. King County leads all counties with more than 7,500 new units, or approximately one-third of the state’s total housing increase.

Information on OFM’s April 1, 2013, population estimates for the state, counties, cities and towns can be accessed at http://www.ofm.wa.gov/pop/april1/.