FAMID variable category/code information

Hello, I am using FAMID to uniquely identify families within a household according to the Census Bureau’s definition of families, but could not find such variable information anywhere about which category that each code represents.

My end goal is to construct a data format that will be submitted to NBER TAXSIM from the IPUMS-CPS. For this purpose, I need to use detailed family-related information and have a unique family identifier. Where would I be able to find this information? Thank you for your help in advance!

FAMID is an identifier variable which, when combined with SERIAL, is a unique identifier of each family within a given year of the ASEC. The values of FAMID don’t have any specific meaning, however FAMID=1 can be used to identify which family within a household contains the householder. The variables FTYPE, FAMKIND, and FAMREL may have some other information that is useful to you.