Map Index - A map showing the relative location of all the FIRM or FHBM panels in a given community, county, or parish. The map index includes the map number (or panel number) and relative location of each panel, as well as an effective date. In those communities, counties, or parishes where all the panels are revised at once, the effective date for the map index is the effective date for the panels in that area. However, in certain communities only some areas (and thus only some panels) are revised at a time, and in these areas different panels may have different effective dates. In these areas, the effective date of the map index is the effective date only for the most recent map panels; older panels that are still current retain their effective date.