Is there a way to delete these older dates, which I no longer have a use for? Can I go to any temp folder directory and delete this info from somewhere?
Yes, on the top right in most of the views (where you can also select the reporting period) in the drop-down is the last point “verwalten”/manage (in earlier version of this post “edit”).
In the opening window you can delete them by a right click (and if I am not mistaken select multiple with the control key).