Last year I thought that there was a variable called INCTANF in the CPS. I did find a variable SRCWELFR, but that only says if a person received it, not the value of the benefit.
An INCTANF variable has never been available through IPUMS-CPS. The closest you can come to such a variable would be to combine the information from SRCWELFR with INCWELFR. INCWELFR reports the respondent’s total welfare income amount. SRCWELFR indicates whether a person received that welfare income from “AFDC/TANF,” “Other,” or “Both AFDC/TANF and other.” Unfortunately, there is no single measure for TANF income.
Hope this helps.