Cal. Rev. & Tax. Code § 2267

In the event that an error or omission occurred in determining the property tax rate which was levied by, or on behalf of, a local agency in either the 1971–1972 fiscal year or the 1972–1973 fiscal year, the maximum property tax rate for such agency for purposes of this chapter shall be the property tax rate which would have been levied, in either such fiscal year, if such error or omission had not occurred.