I apologize for the inconvenience. We strictly recycle reporting data online after 1 year of being in your history. I will change the format of this post to an 'Idea' for future product enhancement potential.
It seems to me that you still have the data needed stored to generate such a report.
We have webinars going back to 2013 - I can still access the attendee list for these webinars.
It would be really useful to be able to generate a session overview report for all the webinars we have paid you to host.