Spatial Insights has announced the release of a block centroid database based on the 2000 Census.
The block centroid database is available by county, state or nationwide. In addition to the coordinates and census identifiers, total population and the number of housing units are included with each of the block cetroids. There are over 8.2 million block centroids nationwide. This contrasts with the roughly 208,000 block groups that provide complete coverage of the US.
The block centroid data are available in MapInfoTM .tab, ESRI .shp, dBase, and delimited text file formats. Additonal formats can be provided on an as-needed basis. Block boundaries are also available from Spatial Insights.
As a derivative product, Spatial Insights has also developed a population-weighted block group centroid file. In this file, the centroid of the block group is defined on the basis of the geographic and demographic characteristics of the census block centroids. This database is useful for visualizing the true population center of a block group. Information about the population-weighted block group centroid file is available at: