NHGIS Updates

Below is a list of significant changes made to the NHGIS database and documentation.

May 2008:  1990 census block summary data (STF1) have been added.  Also, data were corrected in the 1970 County file (CNG4H). 

April 2008:  New release of GIS boundary files.  The files now include a new GISJOIN field to be used for joining attribute data retrieved from NHGIS.  The new GISJOIN field is saved as a string field.  The older GISJOIN (now GISJOIN2) field was preserved.  The following GIS boundary files were updated:

• American Indian area, Alaska Native area, Hawaiian home land
• AITS
• Block
• Block Group
• Congressional District
• Consolidated Metropolitan Statistical Area
• County
• County Subdivision
• Minor Civil Division
• Metropolitan Statistical Area / Consolidated MSA
• New England County Metropolitan Area
• Place
• Primary Metropolitan Statistical Area
• Standard Consolidated Statistical Area
• Standard Metropolitan Statistical Area
• State
• Census Tract (includes 1980 Block Numbering Areas)
• Trust Land
• Urban Area
• Voting District
• Zip Code Tabulation Area

Also, the following files have two new fields available in the shape file:  SHAPE_LEN and SHAPE_AREA:

• Consolidated Metropolitan Statistical Area
• Metropolitan Statistical Area / Consolidated MSA
• Primary Metropolitan Statistical Area
• Standard Consolidated Statistical Area
  
• Standard Metropolitan Statistical Area

March 2008:  New 1980, 1990 and 2000 boundary files released

Using the 1992 TIGER file, the following boundary files were created and released:

•  1980 Minor Civil Divisions
• 1980 Places
• 1980 Block Numbering Areas (Packaged within the 1980 census tract files)
• 101 and 103 Congressional Districts

*Please note – due to some data corruption in the original 1992 TIGER file, some areas of the country could not be extracted and released.*

Using the 2000 TIGER-LINE UA file, the following files were created and released:

• 1990 and 2000 American Indian Area/Alaska Native Area / Hawaiian Home Lands
• 2000 American Indian Tribal Subdivision
• 1990 and 2000 Census Block Groups
• 1990 and 2000 Census Blocks
• 106 Congressional District
• 1990 and 2000 County Subdivisions
• 1990 and 2000 Places
• 2000 Trust Lands
• 1990 and 2000 Urban Areas
• 1990 and 2000 Voting Districts
• 2000 ZIP Code Tabulation Areas (ZCTAs)

 March 2008:  NHGIS data correction.  Data disseminated by NHGIS that exceeded nine characters were truncated.  The data most affected by the truncation were aggregate totals e.g. aggregate income total for the state of New York.  This issue has been corrected.