California pending home sales in May increased 12% from one year ago, the first such gain in 18 months, according to the California Association Realtors. Existing home sales dropped 15.3% across the nation. But in California, May pending home sales — an indicator of the future performance of a market — marked the first yearly increase since November 2009 and the largest since August 2009. CAR President Beth Peerce said May numbers show home sales could be higher in the second half of the year. “May’s increase in pending sales is consistent with our expectation that home sales in the second half of 2011 should be higher compared with the second half of 2010, and as a result, annual sales for all of 2011 should match or exceed last year’s annual pace,” Peerce said. Not all areas of California felt relief, however. Distressed home sales accounted for 90% of the market in Madera County, just north of Fresno. It’s an increase from 69% one year ago. The sale of distressed properties in California neared half of the market, accounting for 48% of all transactions up from 46% one year before. Of the distressed property sales, 28% were REO, and 19% were short sales. Write to Jon Prior. Follow him on Twitter @JonAPrior.