California's unemployment rate increased slightly to 8.7 percent in July, the first such bump since the spring of 2011, state officials announced Friday.

The rate increased two-tenths of a percentage point, up from 8.5 percent in June, according to the state Employment Development Department.

However, the state remains on an overall positive trend and the slight increase could be a statistical aberration, said department spokesman Kevin Callori. July tends to be more volatile because of summer seasonal employment and because recent graduates are seeking jobs.

"It's definitely a departure from the prevailing trend because we had 23 straight months of decreases," he said. "We always caution people not to look at a particular month and focus on the trend. We've dropped quite a lot since last year."

The rate was 10.6 percent in July 2012.

California's rate continues to exceed the nation as a whole. The U.S. unemployment rate dropped slightly to 7.4 percent for July.

Some 1.6 million Californians remained unemployed in July. That is up 29,000 over June, but down by 328,000 compared with July of last year.

The state added more than 38,000 nonfarm payroll jobs in July despite the increase in the rate.

"That's the largest payroll job gain since October of last year and we've experienced 25 consecutive months of payroll job growth," Callori said.