Aug. 11--The growth state is officially shrinking.

Hit by a double-whammy of the housing crash and the recession, Florida has lost population for the first time since the demobilization of hundreds of thousands of soldiers after World War II.

University of Florida demographers will report Friday that the state shed about 50,000 residents between April 2008 and April 2009. That should knock the number of Floridians down a notch from the previously reported 18.3 million.

It's the first time since 1946 that Florida has been a net population loser. Even during the Great Depression, new residents swept into the state in search of work and leisure. But the severe housing contraction, combined with the sputtering of Florida's job creation machine, has eclipsed the state's former gravitational pull.

"You've had families with kids move out when housing prices went up too high," said UF economist David Denslow. "And with construction down, immigrant workers have left."

The university's Bureau of Economic and Business Research relies mainly on electric company connections and disconnections, supplemented by building permit data, to estimate population changes.

In the Tampa Bay area, St. Petersburg's Progress Energy reported a net loss of 8,000 electric customers from the first three months of 2008 to the same period in 2009. Tampa Electric lost about 2,200 customers in the first half of this year compared with a year earlier. UF tweaked the numbers on the theory that some of the lost customers didn't leave the state but moved in with friends or family.

"We've got plenty of rooftops to spare. We just don't have the bodies to put in them," said University of Central Florida economist Sean Snaith.

The latest population numbers back up a trend noted earlier by the U.S. census. Using estimates through July 2008, the federal government said Florida had a net loss of 9,286 domestic residents. If it hadn't been for 77,427 immigrants, mainly from Latin America, the state's population would have fallen last year.

Those immigrants haven't shown up in the same numbers this year, Denslow said. Not only have thousands of Mexican construction workers left, but Colombians who fled violence and instability in their county in the 1980s and '90s have been returning to South America.

Most economic forecasters expect Florida's population dip to be short-lived. Scott Brown, chief economist for Raymond James Financial in St. Petersburg, sees it as a one-year anomaly. But it's a stunning one in a state that has been so reliant on surging population.