Cal. Ins. Code § 923
The commissioner shall require every insurer which is required to file an annual or quarterly statement to use the statement blanks and instructions thereto for the appropriate year adopted by the National Association of Insurance Commissioners. The statements shall be completed in conformity with the Accounting Practices and Procedures Manual adopted by the National Association of Insurance Commissioners, to the extent that the practices and procedures contained in the manual do not conflict with any other provision of this code. The commissioner may make changes from time to time in the form of the statements and the number and method of filing reports as seem to him or her best adapted to elicit from the insurers a true exhibit of their condition. The commissioner shall notify each insurer of any changes from the National Association of Insurance Commissioners' statement blanks which the commissioner has determined pursuant to this section to be appropriate.
Ca. Ins. Code § 923