SPMNUMCHILD
is defined in IPUMS as “the number of children in the family unit.”
It corresponds to SPM_NumKids
in the raw ASEC, which also defines it as “SPM unit’s number of children.”
As SPM reports count the child poverty rate as the poverty rate for people under age 18, I assumed that would be the threshold for defining SPMNUMCHILD
. However, when I counted the number of person records under age 18 per SPMFAMUNIT
, it didn’t match SPMNUMCHILD
. For example, SPMFAMUNIT
1096001 in the 2019 ASEC shows SPMNCHILD
of 0, yet it includes CPSIDP
20190203952801 which is AGE
17.
The threshold doesn’t seem to be age 17 either. For example, SPMFAMUNIT
65001 shows SPMNCHILD
= 2, yet it includes only an 11-, 17-, and 41-year-old.
If not defined by age, how is SPMNUMCHILD
defined?