Utah's economy contracted sharply in the final months of last year as mounting job losses that had been centered in construction finally spilled over to other sectors.

"Using the number of jobs lost as an approximation, I would say that our economy declined about 1.5 percent in the fourth quarter," Wells Fargo bank economist Kelly Matthews said Friday.

"If there were a fourth-quarter gross state product, I think it would have been about a 3 percent real rate of decline," Jeff Thredgold, an economist who consults for Zions Bank, said Friday.

Economists say job gains and losses are the best monthly indicator to measure Utah's performance.

Earlier this month, the state Department of Workforce Services said Utah lost 24,600 jobs in the 12 months ended Dec. 31, pushing the unemployment rate to 4.3 percent, a 43-month high.

There is no official quarterly estimate of Utah gross domestic product, and the official calculation of Utah's economic output in 2008 won't be available until June when the U.S. Bureau of Economic Analysis puts out its annual gauge of state GDP.

Whatever the Utah figure turns out to be, it's certain to show the economy shrank considerably from 2007, when GDP advanced 5.3 percent, according to BEA figures.

"Anybody who thinks Utah is isolated from what's going on outside the border only has to look at the data," Thredgold said.

"The unemployment rate in all 50 states went up in December and unemployment in all 50 states was a higher rate than in December 2007," Thredgold said.

Driving Utah's economy into reverse were weak consumer confidence, faltering retail sales, weak housing figures and turmoil in credit markets, Matthews and Thredgold said.

For most of the year, most of the jobs lost in Utah were in construction. Beginning in November, economists saw evidence the losses were spreading to other sectors.

"It's expanded from residential construction to everything up and down the street, and that's what we are facing as we go into 2009," Matthews said.

pbeebe@sltrib.com