Actually, we have 2 pages in your history to review your offered swaps ("unused" and "margin" swaps) which shows your swaps that were:
-Unused by traders
-Used in a margin position

As well as time of opening and closing, and rate.

This should help you calculate required rate.

At the moment we provide history of FRR via API, which is not very convenient, but can still be informative. I hope to have a FRR hourly history ready soon (read: when we have time to pull this)

Thank you
Raphael