I am trying to retrieve data for Rockingham Country, VA. The code listed says it is 1650 but that is definitely not correct given the data I am getting. Do you know if that code is correct? Thanks.
There are a few things to note about county data in IPUMS. Using IPUMS USA, COUNTY must be used in combination with one of the STATE variables (STATEICP, STATEFIP). Additionally, in general, counties are unavailable in public-use microdata from 1950 onwards. Identifiable counties after 1950 can be found in this spreadsheet. Note that Rockingham Country, VA is not in this spreadsheet, and is therefore unavailable after 1950.
Similarly with IPUMS CPS, to preserve respondent confidentiality, not all counties are identified in COUNTY. Again, it appears that Rockingham Country, VA is not identifiable in the data.
The results you see for code 1650 are likely from Warren County, OH and Sumner County, TN.