San Diego County's jobless rate fell slightly in April, supported by tourist industry summer hiring increases and a shift in construction jobs.

The seasonally unadjusted unemployment rate was 3.7 percent in April, according to the California Employment Development Department. The figure is down 0.2 percentage points from March's 3.9 figure, and 0.5 percentage points better than the 4.2 percent rate predicted for this time last year. San Diego County's rate is better than California's unadjusted rate of 4.8 percent and the United States' unadjusted rate of 4.5 percent. Unadjusted jobless rates don't account for seasonal employment changes, such as summer or holidays.

Gary Knight, president and chief executive officer of the San Diego North Economic Council, said he hasn't heard of any major hiring surges in local tourist-related business.

"They are expecting increases, but nothing dramatic," he said.

Locally, all major North County cities have unadjusted jobless rates below the state average and below their rates from last year. The cities of Carlsbad and Encinitas had the lowest rates, at 2.5 percent, followed by Oceanside and San Marcos at 3.5 percent. Vista had the highest unadjusted rate, but still low overall, at 4.4 percent.

For California, the state gained 21,000 payroll jobs compared with March, with tourism-related jobs up 14,300. San Diego County's economy gained 3,200 jobs last month and followed the state trend with the biggest increases in the tourist-related leisure and hospitality industry, the area that includes hotels and restaurants. Leisure and hospitality gained 1,900 jobs last month, followed by 600 new construction jobs and 500 new jobs in education and health care.

Alan Gin, a University of San Diego economic professor, said he was surprised that construction jobs grew while the local housing market shrank. New housing permits for single-family and multifamily housing units were down 41 percent, from 4,818 permits to 2,836, for the first quarter of this year, compared with the same time in 2005. In contrast, the value of new construction permits grew 206 percent, reaching almost $200 million from last year's almost $65 million. Construction projects are assessed by dollar value, Gin said, and not the number of permits, such as homes and condominiums.

"Construction has shifted from residential to commercial," Gin said.

San Diego North Economic Council President Knight said the new unemployment statistics pleased him and the tourism numbers could grow if high gas prices cause residents to spend more time seeing local sights. But there could be trouble in the area's employment future if the area doesn't produce more educated students and workers.

"I'm worried companies will relocate to places with more emphasis on math and science," he said. "We must grow our own companies locally."