(a) The department shall update and provide a revision of the plan to the Legislature by January 1, 2006, by January 1, 2009, and every four years thereafter, which shall be included in the annual report required by Section 50408. The revisions shall contain all of the following segments:

1. (1) A comparison of the housing need for the preceding plan period with the amount of building permits issued and mobilehome spaces created in those fiscal years.
2. (2) A revision of the determination of the statewide need for housing development specified in subdivision (b) of Section 50422 for the plan period.
3. (3) A revision of the housing assistance goals specified in subdivision (c) of Section 50422 for the plan period.
4. (4) A revision of the evaluation required by subdivision (a) of Section 50422 as new census or other survey data become available. The revision shall contain an evaluation and summary of housing conditions throughout the state and may highlight data for multicounty or regional areas, as determined by the department. The revision shall include a discussion of the housing needs of various population groups, including, but not limited to, elderly persons, disabled persons, veterans, large families, families where a female is the head of the household, and farmworker households.
5. (5) An updating of recommendations for actions by federal, state, and local governments and the private sector which will facilitate the attainment of housing goals established for California.

6. (6) For the next revision of the plan on or after January 1, 2020, and each subsequent revision thereafter, a 10-year housing data strategy that identifies the data useful to enforce existing housing laws and inform state housing policymaking. In developing this data strategy, the department shall establish a workgroup that includes, but is not limited to, representatives from the Department of Technology, metropolitan planning organizations, local governments, relevant academic institutions, and nonprofit organizations with relevant expertise selected by the department. The strategy shall include, but is not limited to, the following:

   1. (A) An evaluation of data priorities.
   2. (B) A strategy for how to achieve more consistent terminology for housing data across the state.
   3. (C) An evaluation of the costs and benefits of, and the ways the department could support, a more integrated digital land use management system, building permit application management system, and other tools that would minimize resources needed for jurisdictions to submit required data.

   4. (D) Information that must be reported under paragraph (2) of subdivision (a) of Section 65400, including, but not limited to, information that:

      1. (i) Supports enforcement of laws, policies, and informs efforts to preserve existing affordable housing stock.
      2. (ii) Supports enforcement of laws, policies, and informs efforts to protect tenants, and ensure habitability of existing housing stock.
      3. (iii) Provides a better understanding of housing project appeals, approvals, delays, and denials, including any relevant data from courts and other state departments.
      4. (iv) Provides an understanding of the process, certainty, cost, and time to approve housing and affordable housing projects.
   5. (E) An assessment of the quality of data submitted by annual reports and recommended changes to annual report requirements and technical assistance based on this assessment.
   6. (F) An assessment of the nature and cost of staffing and technology required for the department and local governments to meet data goals and requirements over the 10-year strategy period.
   7. (G) Information that is useful to enforce state and local housing law and policy, including, but not limited to, enforcement of anti-rent gouging and just cause for eviction policies and ordinances.