I am trying to make tract-level thematic maps for several indicators (e.g. unemployment, median family income etc.).
In the KML and SVG files I am using (including that obtained from TIGER) the 11 digit GeoID10 seems to be the best column through which I can merge data pertaining to the census tracts either by using the "GEO.id2" field from ACS data downloaded as CSV from FactFinder or through a concatenation of "state","county","tract", fields retrieved via the API.
Is there a different key I should be using for tract-level data? This seems to work when making chloropleth maps using the same methods used for making US county-level thematic maps with FIPS (as seen here http://flowingdata.com/2009/11/12/how-to-make-a-us-county-thematic-map-using-free-tools/ )
Thanks in advance for any help.
Voting on Ideas
Vote for your favorite ideas by clicking on the up arrow.To undo an upvote, simply click the arrow again. This second click removes your vote.