Minimum II of 2 but HTML report has no further information

In nested loops, II of outer loops will be two since the exit condition of the inner loop and the outer loop need to be evaluated in one cycle if you want II of one on the outer loop, and that will create a very large critical path and significantly reduce operating frequency. This issue does not necessarily result in lower performance; however, you can merge your loops manually into one to achieve II of one. There should be a note about this in the report at the bottom if you click on the line with the II info, but I don't remember exactly.