Where do Californians go when they leave?

New Census Bureau migration data for 2018 shows folks who leave the state are likely to end up west of the Mississippi River.

Here’s what my trusty spreadsheet tells me about where 691,145 Californians who left for other states now call home.

In raw terms of people moving, the top spot for Californians is Texas, which got 86,164 Californians in 2018. Next came Arizona (68,516), Washington (55,467), Nevada (50,707), and Oregon (43,058). All told, California had the most exits among the state and that wave grew by 4% in a year.

Texas also had the largest “net gain” from California. You know, more ins than outs: 48,354. Next was Arizona (34,846), Nevada (28,274), Oregon (19,008), and Washington (17,460).

Or look at the comings and goings as a ratio of ins to outs.

Tiny Idaho wins this race with 497 arrivals from the Golden State for every 100 former Potato State residents who moved to California. Next was South Carolina (247 ins per 100 out); Texas (228); Nevada (226); and Arizona (203).

Now folks do move to California: 501,023 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 a five-year low. And, by the way, only Texas and Florida drew more in.

The No. 1 state new Californians came from was Washington (38,007); then Texas (37,810); New York (34,848); Arizona (33,670); and Oregon (24,050).

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California’s biggest “net gains” (more ins than outs) are decidedly eastern: No. 1 is New York (9,593); then Illinois (5,647), Ohio (5,200), Massachusetts (3,628), and Maryland (3,118).

And if you look at my “in/out ratio,” you see California does best with West Virginia, losing 42 for every 100 arrivals; then Delaware (48), North Dakota (54), Alabama (58), and Connecticut (60).

Remember that California’s huge population of 39.1 million residents means it’s often near the top of any state ranking, good or bad.

For example, 34.2 million Californians did not move — largest count among the states. By accounting for the state’s size, that’s still high: it’s 87.5% of the population, 10th highest among the states. Another 4.1 million Californians moved within the state, also the largest count among the states. But as 10.5% of the population, it’s the 17th lowest share.

This kind of math also means that despite all the chatter about an “exodus,” the 691,145 departures represent just 1.8% of the population. Only Michigan and Texas lose fewer residents on a percentage base.

California’s problem is arrivals. Only 1.3% of the population moved in from another state last year. No state did worse.