Supplemental Poverty Measure

I am interested to calculate the share of supplemental family unit resources that is derived from various sources, such as earnings, public assistance, private assistance. For such purpose, I first tried to verify for that the sum of INCTOT across SPMFAMUNIT members is equivalent to SPMFTOTVAL. Working with the 2020 dataset, I obtain averages that differ by a couple thousand dollars. I’m writing to ask what I might be doing wrong.

Thank you.

The sum of INCTOT across SPMFAMUNIT members is equivalent to SPMFTOTVAL. You might be getting different values if you aren’t accounting for observations that are not-in-universe (NIU). INCTOT values of 999999999 do not represent earnings but rather observations that are NIU. The Universe tab for INCTOT shows that these are cases of children under 15 years of age. Dropping these NIU (INCTOT = 999999999) and Missing (INCTOT = 999999998) cases should produce estimates for INCTOT across SPMFAMUNIT that are equivalent to SPMFTOTVAL.