I am working on county-level analysis, and for some reason, it appears that Westechester County data is not available in 2000 and 2010 (using the extract system). I understand that the county variable changed over the years, and have tried many different iterations to try to locate the Westchester County code (1190, within County, Countyfips, trying to combine Cities to recreate the region, different samples, etc.). Any help would be much appreciated! Thank you!
Looking at the map of 2010 and 2000 PUMAs (see PUMA for a description of how these geographic units are defined), it appears that Westchester County is unidentifiable due to Heritage Hills, Butlerville, and parts of other area towns being included int he PUMA just north of Westchester County. If you are okay with excluding these areas from Westchester County you can construct the remainder of the county in 2000 with PUMAs 3400, and 3501-3505, and in 2010 with PUMAs 3102-3107.
I hope this helps.