I requested an extract of IPUMS USA data for the 2019 ACS. Looking at counties, only 22 or the 62 counties in New York are specified. The other counties appear to be listed with a county value of NA. I’ve run into this with other states. It doesn’t seem to be strictly by population as Richmond was included but Westchester was not. Does anyone know the reason for this and whether there is a workaround to get any county?
Counties are not provided in the Census Public Use FIle. IPUMS crosswalks PUMAs with counties and makes that match on their end in cases where a single, or multiple PUMAs nest within a county. In many cases those geographies do not nest well, so counties are unable to be identified.
As @Insights_Team_Opport notes, not all counties are identified in the public use ACS microdata. More information on this is available in this blog post from a former colleague of mine; you can download a spreadsheet of identified counties in the microdata from the COUNTYFIP variable description. A quick note that COUNTYFIP should be read in with STATEFIP to uniquely identify counties. Depending on your research application, you may be more interested in using IPUMS NHGIS, which provides aggregate data at lower levels of geography (including all US counties).
Thanks for the clear answer. I have looked at the PUMAs within counties before so that makes perfect sense.
Thanks for the additional info. I’ll check it out.