Prince William County, which added jobs faster than any other large county in the United States in the 12 months ended March 2004, slowed down a bit in the months that followed. Still, it remained one of the nation's fastest generators of jobs.

In the 12 months ended March 2004, the county added jobs at an 8 percent rate, according to Labor Department data, to rank No. 1 in the nation for job growth. According to recently released data for the 12 months ended September 2004, the pace of job growth dipped to 5.8 percent -- still a roaring rate, but only enough to rank No. 7 among counties with 75,000 or more jobs. Similarly, job growth in Loudoun County, which ranked No. 7 on the March list with 5.5 percent growth, retreated slightly to 5.3 percent and the No. 9 slot.

The rate of growth tells only part of the jobs story. Those two counties didn't generate as many new jobs as bigger Washington area jurisdictions, such as Fairfax County. But because they started with fewer jobs they were able to generate bigger gains in percentage terms. In Loudoun and Prince William, much of the growth has been driven by a mix of construction, retail, and other jobs serving the counties' rapidly growing populations. Another factor is the arrival of information technology and other companies in more distant suburbs of Washington, as they seek more affordable office space and proximity to employees' homes.

Those trends continue, but apparently at a slightly slower pace. Meanwhile, other jurisdictions -- such as Rutherford County, Tenn., near Nashville, and Clark County, Nev., which encompasses Las Vegas -- have revved up their job creation engines.

-- Neil Irwin