The Excel option will print the file being accessed providing the report calling it is based on a single – level database.  The database is printed without modification, and that means that the internal fields like “uniq_key” will also be included in the excel file.  When there are multiple databases included in the report, and there are filters and queries involved, the excel button will actually print to a text file that looks like the report.  The user can then convert to an excel file if they wish.