Possible MISH coding errors in 2022 ASEC (for longitudinal participants)

I’m working with ASEC files from 2000 to 2022. I’m coding first and second CPS spells (SPELL), as a way to generate new participant IDs. SPELL==1 for MISH of 1-4; SPELL==2 for MISH 5-8. I’m also then recoding MISH so that the range for all is 1-4. This way, CPSIDP + SPELL + MISH (recoded) uniquely identify observations (I did this for work with the BMS data). But I’m having issues generating SPELL, because it seems that for some participants of two consecutive ASECs, in 2021 and 2022, the MISH is the same. So, for example, person A participated in the 2021 ASEC, and it represented her 4th month in sample. Person A is then shown again, with a second ASEC record, for 2022, but it has her month in sample as 4, when it should be 8. Right? So I’m unable to distinguish CPS spells (SPELL) for certain recent longitudinal participants. I’m attaching a sample of observations with this problem. In these cases, race, sex, and age values match up across the two records.

It feels like someone would have noticed this by now. So I’m wondering if it’s just something I did wrong, or am misunderstanding. :confused:
asec_sample_obs_mish_error.xlsx (10.2 KB)

You are not misunderstanding the MISH variable or month-in-sample concept; this is an error in the original data. This issue has been identified by the IPUMS CPS team in every even-year CPS-ASEC file since 2016 and has been fixed up to the 2020 ASEC, with a fix for the 2022 sample now in the works. The description tab for MISH notes that records in the Census Bureau CPS-ASEC PUMS files in these years have month-in-sample values that do not correspond to these record’s values in the March basic file. IPUMS CPS corrects the March basic monthly respondent’s month-in-sample values to match the March basic monthly file values. Specifically, the fix adds 4 to 2022 ASEC MISH values under 5.

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Thanks so much! I suppose then I can make this fix on my own; seems easy enough.