California had 190,122 more residents move out to other states in 2018 than arrived — a 38% jump in a much-discussed outmigration benchmark, new Census Bureau data shows.

More ins than outs — or what experts call “net domestic migration outflow” — is frequently blamed on California’s high cost of living, from housing to high taxes. And the state’s liberal politics have soured some conservatives on Golden State living.

Census figures show 691,145 Californians last year left for other states — the largest loss nationally and up 4.6% in a year. It was the seventh consecutive annual increase.

But note that as a percentage of the state’s 39.1 million residents, these exits represent just 1.8% of the population and only two states — Michigan and Texas — have smaller departure rates.

California’s real population challenge is getting other Americans to move here.

Yes, 501,023 new residents arrived from other states in 2018. And yes, that’s the third-highest inflow among the states. But that’s down 4.2% in a year and is a five-year low. Plus, it’s the nation’s worst rate of attraction: Only 1.3% of the state’s population moved last year to California from elsewhere in the U.S.

Population growth isn’t just a popularity contest. While some will complain about overcrowding, California businesses find themselves short of workers. And population patterns have national political consequences as the 2020 Census will determine how congressional seats are divided among the states.

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So these growing departures and slowing arrivals pushed up California “net outmigration” by 52,227 last year to 190,122. Only New York had a larger gap between residents coming and going. Even on a percentage basis, California has the ninth-worst outflow.

Arrivals from foreign lands boosted California’s population: 283,649 came from other nations — legal or otherwise. That’s the largest immigration flow nationally, and these arrivals represent 0.73% of the population, ninth-highest among the state.

These losses of friends, family and co-workers to other states is a key reason California’s population growth has slowed. In 2018, by this math, California’s population grew by just 28,905. That ranks just 19th among the states, and this 0.07% percentage gain ranked No. 38. Texas had the largest gain in residents 408,850.

Tiny Idaho, the 12th least populous state, was the fastest growing in percentage terms: Its 40,574 population gain — growth in numbers topping giant California — was 2.4% of its residents.