Overture Search Volumes

Different figures on monthly report to search tool

[gypsychild]

I have just noticed there are quite different figures showing up for total monthly searches for March on the Overture Search Term Suggestion Tool compared with those on my Client Activity Report Summary. Almost all of the figures on the latter are higher, some nearly as much as 50%.

Is this just me and if not, can anybody shed any light on this? I would ask Overture direct, but having had problems with them in the past, cannot again bear to go through the frustration of them either apparently not understanding my point or not responding at all.