L.A.’s unemployment rate held steady at 8.1 percent for August even as the county gained nearly 18,000 jobs as some schools reopened after summer vacation, according to state figures released Friday.

The Employment Development Department reported that the jobless rate has held steady since June. It’s down from 9.9 percent a year ago, but still exceeded the state average of 7.4 percent and was two full percentage points above the national average of 6.1 percent.

More Los Angeles County residents reported they were working in August, but that was offset by more residents looking for work.

August’s employer payrolls grew by 17,600 jobs, or 0.4 percent. The increase partially offset July’s sharp drop, but the total payroll figure was still shy of the June peak of 4.2 million. When adjusted for seasonal factors, the county actually added about 25,000 jobs, according to an analysis of the data by Beacon Economics of Los Angeles.

The education sector posted the biggest gains in August, adding about 8,000 jobs as some schools restarted after summer recess. Most schools still reopen in September, so next month’s jobs report should show even bigger gains in education.

The other sector with big gains in August was professional and business services, up 6,600 jobs. The government and entertainment sectors also posted slight job gains.

The professional and business services category was the biggest gainer in the closely watched year-over-year payroll employment figures, adding 32,000 jobs.

“We’ve been seeing steady gains in hiring for administrative positions,” said Iyda Kelati, Torrance branch manager for international staffing firm Adecco. Kelati said the retail and retail distribution sectors have been hiring the most administrators as they gear up for the holiday shopping season.

Health care/social assistance gained 16,600 jobs over the past 12 months, while leisure/hospitality and construction also posted significant gains. Manufacturing was the only sector to post a net job loss, shedding 15,500 jobs.

Overall, employers in the county added a net 69,000 jobs over the past 12 months, for a growth rate of 1.7 percent.