The number and amount of withholding exemptions allowed shall be based upon the persons claimed in a withholding exemption certificate in effect under Section 13040, except that if no such certificate is in effect, the number of withholding exemptions claimed shall be considered to be zero.

(Added by Stats. 1980, Ch. 1007, Sec. 64. Operative July 1, 1981, by Sec. 67 of Ch. 1007.)