I have found that 24 of the 2010 ACS occupation codes that change between the 2010 and 2018 classification systems are not sampled in the CPS after April 2012 (e.g. 2960, 6430, 7930, 8840, 9500). Does anyone know why this might be? Clearly these occupations are redundant by 2018 (as these codes are changed in the next classification system) but it is puzzling that so many are last sampled in exactly the same month, April 2012.
The CPS altered their occupation coding scheme in 2012, which simply grouped a few small occupations together. It’s not very well documented, but there’s evidence of the change by looking at the CPS codebooks starting in May 2012—the appendix listing Occupation Codes notes “Beginning May 2012”. The edited list of CPS codes with a crosswalk to the 2010 SOC used to be listed at this page: https://www.bls.gov/emp/documentation/crosswalks.htm; however, it looks like it has been updated since the 2018 SOC was introduced. If you need this, I’d recommend reaching out to the BLS directly for an older version of the national employment matrix CPS-to-SOC crosswalk.