California Code, Government Code - GOV § 7909

No later than May 1 of each year, the Department of Finance shall notify each local agency of the change in the cost of living or change in California per capita personal income, whichever is less, and population for each local agency for the prior calendar year.

No later than May 1 of each year, the Department of Finance shall notify the Department of Education and the Chancellor's Office of the California Community Colleges of the change in the cost of living or change in California per capita personal income, whichever is less.  These agencies shall inform the school districts, county superintendents of schools, and community college districts for which they are respectively responsible.