Santa Clarita’s jobless rate fell dramatically in September, dropping to 6.2 percent from 6.9 percent in August as teachers returned from summer vacation.

But the return to work of Santa Clarita’s teachers doesn’t explain the area’s year-over-year job gains.

Last September, Santa Clarita’s unadjusted jobless rate stood at 7.6 percent. One year later, it’s 1.4 percent lower.

Across Los Angeles County, the seasonally adjusted unemployment rate improved by 0.4 percent over the month to 10.6 percent in September. (The adjusted rate adjusts for returning teachers, so the 0.4 percent improvement is “real”).

Teachers accounted for the biggest job gains in the county over the month, with 13,200 positions added within the local government sector. Private education added another 11,500 jobs to payrolls.

The trade, information, professional services, financial and hospitality sectors made modest gains, while state government constricted by 1,100 jobs in L.A. County and health services cut 1,300 positions.

The construction industry posted the biggest job losses in the county during September, slashing 3,400 jobs since August.

California’s seasonally adjusted rate improved to 10.2 percent from 10.6 percent in August, while the nation’s rate fell to 7.8 percent in September from 8.1 percent in August and 9 percent in September 2011.