How the 2007 TIGER/Line Shapefiles are Organized
The organizational structure of the TIGER/Line Shapefiles is based on the hierarchical relationship of geographic entities.
Nation-Based Files - Located at the US - Nationwide Data Level
Entities that are defined independently from states and counties, such as American Indian Areas, are available in nation-based shapefiles that encompass the entire country. The following layers are included:
- American Indian/Alaska Native/Native Hawaiian Area (Census 2000 and current)
- American Indian Tribal Subdivision (Census 2000 and current)
- Combined New England City and Town Area (current)
- Combined Statistical Area (current)
- Metropolitan Division(current)
- Metropolitan/Micropolitan Statistical Area (current)
- New England City and Town Area (current)
- New England City and Town Area Division(current)
- State and Equivalent (Census 2000 and current)
- 3-Digit ZIP Code Tabulation Area (Census 2000)
- 5-Digit ZIP Code Tabulation Area (Census 2000)
State-Based Files - Located at the US State - Statewide Data Level
Entities such as school districts and congressional districts that are defined within states and can cross county boundaries are represented in state-based shapefiles. The following layers are included:
- Alaska Native Regional Corporation (Census 2000 and current)
- 110th Congressional District
- 108th Congressional District
- 106th Congressional District
- Consolidated City (Census 2000 and current)
- County and Equivalent (Census 2000 and current)
- Place (Census 2000 and current)
- 1-Percent Public Use Microdata Area (Census 2000)
- 5- or 10-Percent Public Use Microdata Area (Census 2000)
- Elementary School District (Census 2000 and current)
- Secondary School District (Census 2000 and current)
- Unified School District (Census 2000 and current)
- State Legislative District—Lower Chamber (Census 2000 and current)
- State Legislative District—Upper Chamber (Census 2000 and current)
- Urban Growth Area (Census 2000)
County-Based Files - Located at the Individual County Data Level
Entities that are defined within counties and do not cross county or state lines such as census tracts, block groups, and blocks are represented in county-based shapefiles (i.e. one shapefile for each county). The following layers are included:
- All Lines (current)
- Area Hydrography (current)
- Area Landmark (current)
- Point Landmark (current)
- Block (Census 2000 and current)
- Block Group (Census 2000)
- Census Tract (Census 2000)
- County Subdivision (Census 2000 and current)
- Subbarrio (Census 2000 and current)
- Traffic Analysis Zone (Census 2000)
- Voting District (Census 2000)
- Address Range-Feature Name Relationship File (current)
- Address Ranges Relationship File (current)
- Feature Names Relationship File (current)
- Topological Faces (2-Cells With All Geocodes) Relationship File (current)
- Topological Faces-Area Landmark Relationship File (current)
- Topological Faces-Area Hydrography Relationship File (current)
American Indian Area-Based Files
The following layers are available by American Indian Area:
- American Indian Tribal Subdivision (Census 2000 and current)
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