Camden saw the greatest population increase in the past decade, closely followed by Rockport and Hope.

Rockland, however, saw a significant decline that the city’s mayor said is cause for concern.

The Census released formal population figures Aug. 12 for states, counties and communities based on the 2020 count. This is the first formal count since 2010.

Knox County’s population increased 2.2% (807 people), reaching 40,607, according to the 2020 Census. The population became slightly more diverse with 95% of the people in the county listed as white, down from 97% in 2010 and 98% in 2000.

Maine saw a 2.6% population increase (33,998 people) from 2010 to 2020, increasing to 1,362,359. The U.S. recorded a 6.3% (about 23 million) increase in 10 years, increasing to 331 million.

Censuses are conducted every 10 years to determine the number of representatives that states will have, and to determine legislative and county political apportionment. The information is also used to determine how federal and state aid is distributed.

Rockland’s population declined by 361, falling to 6,936 in 2020. The city’s population reached a peak of 9,284 residents in 1950 and declined in all but one Census since then.

Details on the demographics of the communities were not immediately available. Details will show the number of people who moved to the community since the prior Census.

Rockland Mayor Ed Glaser said housing pressures are more than just providing affordable housing for people who live here.

“As Rockland becomes even more attractive to people who don’t live here full time, whether they are summer residents, or people who invest in short-term rental properties, we change who is using our limited supply of housing. People who want to live here full time can’t afford it, families can’t afford it, workers can’t afford it.

“I’m not sure what we can do to reverse the trend of the last 20 or more years, but this just shows that what we’ve been doing hasn’t worked. If we continue to lose population, we lose the energy that makes this the place we want to live. Rockland has never been just a summer community, and if it continues, we will turn our back on our history and what has made Rockland the economic engine of the Mid-coast. I don’t like it, we have to turn it around,” Glaser said.

In 1950, Rockland accounted for 33% of the population in Knox County and had multiple representatives in the Maine Legislature. The 2020 figures shows Rockland declined to 17% of the total county population. Rockland currently shares a representative with Owls Head.

The Legislature is expected to come up with a redistricting plan for seats in the House and Senate this fall.

Camden’s population increased the most of any of the Midcoast communities, adding 382 residents, reaching 5,232, according to the 2020 Census.

The following are the 2020 population for Knox County and adjacent towns:

Appleton 1,411, up 7% (95).

Camden 5,232, up 8% (382).

Cushing 1,502, down 2% (32).

Friendship 1,142, down 1% (10).

Hope 1,698, up 11% (162).

Isle au Haut 92, up 26% (19).

Islesboro 583, up 3% (17).

Lincolvnille 2,312, up 7% (148).

Matincus Island 53, down 28% (21).

Monhegan Island 64, down 7% (5).

North Haven 417, up 17% (62).

Owls Head 1504, down 5% (76).

Rockland 6,936, down 5% (361).

Rockport 3,644, up 9% (314).

St. George 2,594, 0% change (3 more residents).

South Thomaston 1,511, down 3% (47).

Thomaston 2,739, down 2% (42).

Union 2,383, up 5% (124).

Vinalhaven 1,279, up 10% (114).

Waldoboro 5,154, up 2% (79).

Warren 4,865, up 2% (114).

Washington 1,592, up 4% (65).

Lincoln County’s population increased by 780 people, reaching 35,237.

Waldo County’s population increased by 721, reaching 39,607. Belfast’s population rose by 270, reaching 6,938.

Portland remains Maine’s most populous city, increasing 3.3% (2,214) to reach 68,408. Lewiston’s population increased by 529 residents to reach 37,121. Bangor’s population dropped by nearly 4% (1,286), falling to 31,753.