California's Population Now Tops 39 Million

New figures released by the California Department of Finance show that the state grew by 346,000 (to July 1, 2015). As in past years, the increase comes from natural births and immigration while more left the state than entered.

2 minute read

December 23, 2015, 8:00 AM PST

By Irvin Dawid


Growth in the nation's most populous state outpaced the nationwide annual population growth rate in the last decade of .73 percent (PDF).

"Birth rates have stabilized but remain below historical averages," notes the press release.

Natural increase, births minus deaths, remains the primary source of the state’s population growth. The natural increase of 262,000 is comprised of 507,000 births minus 245,000 deaths. 

"Births, once nearly 600,000 a year, have been declining in recent years while deaths are climbing as the large baby boom generation ages," writes Dan Walters of The Sacramento Bee.

Net domestic migration was (-61,120), i.e., the difference between people migrating to California from other states and those leaving for other states. As noted in prior posts on California demographic data, the state's high housing costs, particularly for those earning <$50,000, is a major reason why residents leave California.

Net immigration (to/from foreign countries) was 145,027.

Some bullet points from the press release:

  • San Joaquin, Monterey, Santa Clara, Yolo, Alameda, and Contra Costa counties had the largest percentage increases in population, each growing by 1.3 percent or more. Population change ranged from the highest growth rate of 1.6 percent in San Joaquin to -2.6 percent in Lassen. 
  • Los Angeles, San Diego, Orange, Riverside, and Santa Clara counties posted the highest numeric population gains and account for over half of the state's growth. Growth in these counties was due primarily to natural increase, although most of the counties had positive net migration [combined domestic migration and immigration] as well. - San Joaquin, Monterey, Santa Clara, Yolo, Alameda, and Contra Costa.

Walters writes that San Joaquin County had the highest growth rate with 1.58 percent, and Los Angeles County, while below the statewide average growth rate (with .68 percent), had the highest numeric increase, 68,686 people. 

Maps in the 20-page press release [PDF] show statewide demographic growth data, and charts showing individual data for the state's 58 counties. Revisions were made for population data going back to 2010.

Dan Walters explores the political implications of the state's growth in a separate piece.

Wednesday, December 16, 2015 in California Department of Finance Press Release

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