OAKLAND, Calif.— The percentage of California employers that offer healthcare coverage to their employees has plummeted in the past decade. In 2012, 60% of California employers offered coverage to their employees, down from 71% in 2002, according to a survey by the California HealthCare Foundation. Coverage rates, though, varied significantly by company size. For example, 98% of California employers with at least 1,000 employees offered healthcare coverage last year, as did 97% of firms with 200 to 999 employees. On the other hand, only 49% of employers with between three and nine employees offered coverage, while 71% of firms with 10 to 49 employees provided coverage. During the 10-year period, premiums for healthcare plans offered by California employers rose an average of 169.7%, while the state's inflation rate increased 31.5%, according to the survey. The 2012 results are based on 659 interviews conducted late last year with benefit managers. The 2002 coverage figures came from an earlier Kaiser Family Foundation survey.