The Totals row at the bottom of each tab level (Channels, Campaigns, Groups, Keywords, Products, and Creatives) and as well in the reports generated in Marin, are all generated from a separate table. They are not generated by summing up what is seen in the grid for that tab. These Totals should reflect metrics at the Group level, when no filters are applied. When a filter is applied, the Totals row recalculates showing the summation of exactly what is in the grid.
The Totals found on the Keywords tab when no filters are applied shows the Totals at the Group level. This explains why the Totals row shows a higher metric count when compared to the actual total of the Keywords tab. The reason why Group level metrics are higher could be due to multiple factors such as accounting for Content and/or Placements.
When you apply a metric filter (i.e. Impressions, greater than, 0), this recalculates the Totals row to show data seen at the Keyword level (adding up what is currently seen in the grid).
Note: To see accurate keyword level data, you need to apply a filter (e.g. impression >0).
