The 2020 Census resulted in California losing a Congressional seat for the first time in its 170 year history as a state but that loss could have doubled if not for hundreds of thousands of legal and illegal migrants moving to the state.

California’s population growth is so slow-moving it would have needed almost 500,000 more people to keep the lost seat, and it could have lost a second seat had it grown by 284,400 fewer people.

The San Francisco Chronicle reported on the phenomenon, which noted California gained about 1 million new residents from outside the U.S. from 2010 to 2019, the year before the latest Census. In other words, without the state’s annual influx of immigrants, California could have lost even more federal representation.

The Chronicle report said:

The main component of California’s increasing population over the last decade has been the natural increase from the number of births outpacing deaths. Between 2010 and mid-2019, California had nearly twice as many births as deaths, adding about 2.2 million people. While international migration remained strong, overall net migration —both domestic and international — contributed far less to population growth, adding just 110,000 people to the state’s population.

This low number stems from California’s plummeting domestic migration rate, which led to an estimated loss of 2.4 percent of the state’s 2010 population. However, international immigration effectively neutralized domestic migration’s negative effect, adding 2.7 percent of the 2010 population back, meaning total migration added 0.3% to California’s 2010 population by mid-2019.

California’s domestic migration rates have been negative almost every year since the early 1990s, according to the California Department of Finance. After briefly flipping positive at the turn of the century, the numbers dipped, crept up to nearly neutral in 2011 and 2012, and then began a steady downward march, to a current loss of about 260,000 people. That’s the greatest domestic outflux since 1993-1996, when net domestic migration losses exceeded 275,000 four years in a row.

“Most of (California’s) recent migration shift is domestic: a function of residents leaving California for other states,” researchers at the Public Policy Institute of California wrote earlier this week. “While immigration from other countries has declined, it has not changed nearly as much.”

The majority of California’s new residents in 2019 came from 10 countries — China had the most immigrants coming into the state, with about 35,000 moves documented by the Census. Mexico came in second, with about 34,000 migrants, and India was third, with about 19,000 migrants.

The other countries rounding out the top 10 are Japan (13,000), Korea (11,000), Vietnam (11,000), Philippines (11,000), Canada (11,000), Taiwan (6,000), and the United Kingdom (6,000), according to the U.S. Census Bureau for 2019.

The Chronicle reported the Census probably undercounted and California is home to the U.S.’s largest population of illegal migrants.

The PPIC estimates as many as 1.6 million Californians could have been left out of the Census count because they could not reach illegal migrants “and other vulnerable groups.”

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