I have collected census data for a county in Pennsylvania. Data varies from 1999-2010. For my data before 2010, a significant number of blocks do not match up (image below) when I join the data (based on GEOID).
I have joined to 1990, 2000 and 2010 census block groups. There are roughly the same number of block groups, but the GEOID's are always off for maybe 30% of the block groups.
I feel like i'm missing something here... Anyone had trouble with this before?
So I'm offering a bounty now. Basically I just need to be able to join this data with the shapefile block groups from any year... But my guess is that they would best align with 2000.