Geographic Summary Levels

Many layers are associated with shapefiles that have geography classified by Geographic Summary Levels.  This is particularly true about Federal statistical shapefiles.  A shapefile will often include data for only one or a few related summary levels.

Geographic summary levels, or just Summary Levels, are 3-digit codes associated with type of political/statistical geographic areas.  Most of the summary level codes described in this section are based on Census Bureau summary level codes and used as a standard, where possible, throughout CV XE GIS and Situation & Outlook.

Geographic summary levels (partial list)

100 Census Block -- about census blocks: http://proximityone.com/geo_blocks.htm

150 Block Group -- about block groups: http://proximityone.com/geo_blockgroups.htm

140 Census tract -- about census tracts: http://proximityone.com/geo_tracts.htm