Procedure
Follow these steps to obtain block group data in Atlas GIS 4.0:
1. Copy the appropriate blkgrp.xxx files from the Data & Maps CD into a folder.
2. Open the .shp file in Atlas. When the file is converted to a geo file (.agf), it will automatically be linked to its corresponding .dbf file.
3. Open the table and locate the column titled BKG_KEY. This is the column that holds the block group data that will be put into your table.
4. Open the point table you want the block group data to go into. Make sure this table has lat/long columns with coordinates.
5. Define an empty column, BLOCKGROUP, to hold the new data.
6. Navigate to Table > Assign Data By Location
7. Choose the point table for Assign Results To.
8. Choose the linked table that has the block group data for From Containing or Nearest Feature In.
9. Choose the empty column defined to hold the data for Column To Fill.
Expression: BKG_KEY.
10. Click OK
You should now have block groups in your point table that correspond to your point data.