This Product Features and Updates announcement for GPS Insight Pro/Enterprise includes updates for Reports.
Idle Time Summary Report – Custom Metric Data
If you add a metric to a report that uses the same label as another column title in the report, the metric column includes an (M) designation (see below).
Additionally, note that this particular metric data (Max Speed) provides daily summarization data that is averaged for the time period selected; therefore, the values may vary from other report columns with similar labels. In the example below, the Max Speed column on the left shows the maximum speed cited during the report period, whereas the metric column shows the average maximum speed cited during the report period. All other metrics use sum instead of average.