Senator Nunn, like many of his colleagues in the Senate, asked his staff to generate a list of the top ten topics and top fifteen subtopics for the correspondence received during the week. This information helped him to gauge which issues were most important to his constituents. Topics indicated the primary broad subject area addressed in a letter (e.g., defense, labor, social security, etc.) Subtopics indicated a narrower issue area within that topic (e.g., balance budget, iraq-kuwait, national lottery, etc.) This section of CMAP allows researchers to dynamically generate a list of the top fifteen subtopics for a given month and then to view a map showing the geographic distribution for each subtopic in the list. Entries identifiable as case work have been excluded from the result set in order that more legislative issues might be reflected in the top fifteen list. Not every entry with a subtopic can be mapped because some entries do not list a zip code or list inaccurate data in the zip code field. (See the description of data for more information about known data irregularities.) For an explanation of some of the subtopics not related to legislative issues, please see the list of non-issue subtopics.