CA Gov't Code Section 65040.8

The Office of Planning and Research shall develop a housing cost manual which may be used by local agencies in assessing the impact on housing costs of alternative land use proposals and land use regulatory programs of local agencies and as an aid in evaluating private land use proposals. The manual shall present economic and technical criteria for local agencies to use in developing or acting on, or both, general plan elements, zoning regulations, subdivision map regulations, alternative land use proposals and policies, and private land use proposals. The manual shall include a step-by-step program which local agencies may follow, including, but not limited to, sources of data, methods of summarizing and using the data, formulas for evaluating the impacts on housing costs of land use and land use regulatory decisions, and a guideline on how to prepare a single statement of results. The Office of Planning and Research shall complete the housing cost manual required by this section by January 1, 1981.