California Code, Government Code - GOV § 11093

(b) The Controller may, upon request therefor contained in a motion adopted by the City Council of the City of Los Angeles, designate additional statistical areas within the City of Los Angeles, except that the additional statistical areas shall in no event exceed three in number.

(c) For purposes of this section, the San Fernando Valley is all the portion of Los Angeles City that is described as follows:

From a point commencing where the City of Los Angeles most northerly boundary intersects with the Golden State Freeway and following on the city boundary in an easterly direction where that boundary first intersects with the boundary of the City of Burbank;  thence continuing southeasterly along the Burbank City boundary to its intersection with Barham Boulevard;  thence in a southerly direction on Barham Boulevard to its intersection with Cahuenga Boulevard;  thence in a southeasterly direction on Cahuenga Boulevard to Mulholland Drive;  thence along Mulholland Drive to Owen Brown Road;  thence in a southerly direction on Owen Brown Road to its intersection with the Los Angeles City boundary;  thence following the Los Angeles City boundary west and northerly until that boundary intersects with the starting point at the Golden State Freeway.