The nation-based comma delimited relationship files contain a separate record for each unique entity code combination. For example, in the Congressional Districts and Counties file, if the county contains two congressional districts, there will be two records in the file for that county; one for each congressional district.
These files contain only geographic reference codes; they do not include entity names. The codes are right justified and zero filled.
Note: For inter-censal changes to congressional districts, new tables are only generated for states with changes after the initial post-decennial redistricting. No new tables were generated for the 111th or 112th Congresses, for example, because no states made changes to their 110th Congressional District boundaries.