While some California residents opted to leave the state during the pandemic, far fewer people are also moving to the state from other parts of the country, according to new research from the University of California at Berkeley's California Policy Lab.
The amount of people leaving the state has increased by 12 percent between March 2020 and September 2021, a figure roughly on pace with pre-pandemic levels, according to the California Policy Lab.
However, while migration to California generally kept pace with migration out of the state prior to the pandemic, entrances to California have fallen by 38 percent.
"The public's attention has been focused on the so-called 'CalExodus' phenomenon, but the reality is that the dramatic drop in 'CalEntrances' since the pandemic began has been a bigger driver of recent population changes in the state," said Natalie Holmes, the report's co-author, a California Policy Lab research fellow and a Ph.D. student at UC Berkeley.
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The researchers found that all 58 of the state's counties had seen declines in migration from other states, with entrances to California decreasing between 25 and 45 percent in every region of the state.
That rate was even higher in the Bay Area, as San Francisco, Santa Clara and San Mateo counties each saw their out-of-state entrances fall by roughly 50 percent.
The number of people moving away from the state from those counties rose by 34 percent, 26 percent and 15 percent, respectively, according to the California Policy Lab.
"If these trends continue, the implications for California are significant, ranging from federal funding allocations and tax revenues to how many seats we have in Congress," Holmes said. "Population swings can have even more dramatic effects on local jurisdictions."
While data on emigration to California from other countries was not included in the report -- and has supported California's population growth in recent years -- overall growth slowed to such an extent during the pandemic that California's year-over-year population declined in 2020 for the first time in more than a century.
Likewise, while California's population grew between 2010 and 2020, the results of the 2020 U.S. Census found that the state's growth occurred at a slower rate than other parts of the country.
The full report from the California Policy Lab can be found here.