One of the biggest changes in the American population in the last sixty years has been the migration to the Sun Belt. But new data suggests that this boom may have come to an end:

Between 2007 and 2010, Florida lost more people to internal migration than it gained, for the first time since the 1940s. Nevada, too, which had been growing for decades, had a net migration loss of 30,000 in 2009. And Arizona had a net gain of just 5000, way down from 90,000 five years before.

Meanwhile, New York and California both saw their net losses shrink in 2009 by more than half since 2005.

The analysis, based on Census Bureau and IRS data, was conducted by the Carsey Institute at the University of New Hampshire.

What explains the shift? The Sun Belt states, of course, were hit hard by the housing bust that helped trigger the recession and its aftermath. The early aughts housing boom was responsible for much of the growth in places like Clark County, Nev., and Maricopa County, Ariz. in the first place.

But just as important, migration as a whole, which has been on the wane for three decades, has really tailed off since the downturn began.

The economic crisis has limited mobility across the United States, particularly for the less wealthy who are then more tied to existing jobs and homes.

It will be interesting to see whether this trend continues or (1) the Sun Belt will grow again in the future or, in a longer shot, (2) older cities in the Midwest and Northeast (“Rust Belt”) regain some of the population that shifted south and west. In other words, once people have some more freedom to move, what will they choose to do and what social forces will push or pull them in certain directions?