Revenue and Taxation Code section 24251
(a)
The same proportion of a tax for the entire period, determined under the law and rates applicable to the first calendar year which the portion of the period falling within the first year is of the entire period; and(b)
The same proportion of a tax for the entire period, determined under the law and rates applicable to the second calendar year which the portion of the period falling within the second calendar year is of the entire period.
Source:
Section 24251, https://leginfo.legislature.ca.gov/faces/codes_displaySection.xhtml?lawCode=RTC§ionNum=24251.
(accessed Apr. 24, 2025).