This field specifies the county Federal Information Processing Standard (FIPS) code for the Medicare beneficiary.
CCW derives this variable from the last 3 digits of the MBSF monthly state/county FIPS code (source variables called STATE_CNTY_FIPS_CD_01–12).
Values: 3-digit FIPS county code (e.g., 143) or null/missing (if no Medicare enrollment)
https://www.nber.org/research/data/ssa-federal-information-processing-s…
Source: Medicare MBSF
CCW derives this variable from the last 3 digits of the MBSF monthly state/county FIPS code (source variables called STATE_CNTY_FIPS_CD_01–12).
Values: 3-digit FIPS county code (e.g., 143) or null/missing (if no Medicare enrollment)
https://www.nber.org/research/data/ssa-federal-information-processing-s…
Source: Medicare MBSF