Cal. INS § 11665

(a) An insurer who issues a workers’ compensation insurance policy to a roofing contractor holding a C-39 license from the Contractors’ State License Board shall perform an annual payroll audit for the contractor. This audit shall include an in-person visit to the place of business of the roofing contractor to verify whether the number of employees reported by the contractor is accurate. The insurer may impose a surcharge on each policyholder audited under this subdivision in an amount necessary to recoup the reasonable costs of conducting the annual payroll audits.

(b) The commissioner shall direct the rating organization designated as his or her statistical agent to compile pertinent statistical data on those holding C-39 licenses, as reported by the appropriate state entity, on an annual basis and provide a report to him or her each year. The data shall track the total annual payroll and loss data reported on those holding C-39 licenses in accordance with the standard workers’ compensation insurance classifications applicable to roofing operations. The data shall include the number of employers, total payroll, total losses, and the losses per one hundred dollars ($100) of payroll by the employers’ annual payroll intervals as follows:

1 to 4,999
5,000 to 9,999
10,000 to 14,999
15,000 to 19,999
20,000 to 24,999
25,000 to 29,999
30,000 to 39,999
40,000 to 49,999
50,000 to 74,999
75,000 to 99,999
100,000 to 199,999
200,000 to 299,999
300,000 to 399,999
400,000 to 499,999
500,000 to 599,999
600,000 to 699,999
700,000 to 799,999
800,000 to 899,999
900,000 to 999,999
1,000,000 to 1,099,999
1,100,000 to 1,199,999
1,200,000 to 1,299,999
1,300,000 to 1,399,999
1,400,000 to 1,499,999
1,500,000 or more

The report shall also be provided to the Legislature by the commissioner, in compliance with Section 9795 of the Government Code.