Files prefixed with "pb" contain corner point coordinates for all Block maps in a state, files prefixed with "pv" contain corner points for the Voting District/State Legislative District outline maps, and files prefixed with "ct" contain corner points for the Census Tract outline maps. For example, the corner point files for Kansas are:

pbstKScpf.txt  (P.L. 94-171 County Block maps)
pvstKScpf.txt  (P.L. 94-171 Voting District/State Legislative District Outline maps)
ctstKScpf.txt   (Census Tract Outline maps)

Each line in the file represents information for one map sheet. The sheet code is a twenty digit number that matches the bar code number at the lower right of each map sheet. The first three digits are a computer-assigned control number, positions 4 through 8 are a 2-digit FIPS State code and a 3-digit FIPS county code, in this case FIPS state code 20 (Kansas) and FIPS county code 023 (Cheyenne). Positions 9 through 12 give sheet number information. The Index sheet (sheet _000.pdf) is numbered "0000" in positions 9 through 12. Parent sheet "_001" is shown as "0010", and Inset sheet "_A01" is shown as "6501" ("65" is the ASCII code for "A", "66" for "B", "67" for "C" etc.). To obtain the latitude and longitude in decimal degrees, divide the numbers shown by 1 million. The scale is given as the denominator of the representative fraction shown on the map sheetsheet.

• PL94_171 County Block Corner Point Files
  
• PL94_171 Voting District/State Legislative District Corner Point Files
  
• Census 2000 Census Tract Corner Point Files