An inidentified construction workers tends to girder supporters.

PROVO — Utah County ranked No. 4 in the nation for the percentage of new jobs created over a 12-month period.

The U.S. Bureau of Labor Statistics reported Thursday that from September 2010 to September 2011, employment increased in 271 of the 322 largest U.S. counties, including 4.5 percent in Utah's second largest county. Salt Lake County — which saw a 2.8 percent increase — ranked No. 48, while no other Utah county ranked among the top 200.

Topping the list was Williamson County, Tenn., posting the largest increase with a gain of 5.4 percent over the year, compared with national job growth of 1.6 percent. The report stated that within Williamson, the largest employment increase occurred in professional and business services, which gained 1,743 jobs over the year or 9.0 percent.

Conversely, Frederick County, Md., experienced the largest over-the-year decrease in employment among the largest counties in the U.S. with a loss of 2.6 percent.

Jasen Lee Twitter: JasenLee1