U.S. Census Grids (Summary File 1), 2000 contain grids of demographic and socioeconomic data from the year 2000 U.S. census in ASCII and geotiff formats. The grids have a resolution of 30 arc-seconds (0.0083 decimal degrees), or approximately 1 square km. The gridded variables are based on census block geography from Census 2000 TIGER/Line Files and census variables (population, households, and ... housing variables). This dataset is produced by the Columbia University Center for International Earth Science Information Network (CIESIN).
The data in American Standard Code for Information Interchange (ASCII) and Geographic Tagged Image File Format (GeoTIFF) files and maps n Portable Document Format (PDF) and Portable Network Graphics (PNG) formats are available from the NASA Socioeconomic Data and Applications Center (SEDAC).