I don't proclaim to be an expert however I do know CCC+ is...

I don't proclaim to be an expert however I do know CCC+ is better than CCC (just like BBB- is better than CCC+).
So the rate for CCC+ should be better than 11.44%. Might be 10%, might be 10.5%, might be 11%; like I said, around 10% as opposed to 15%.
Considering you posted a graph showing CCC at 11.5% (incidentally it dropped to 11.44% on Jan 10 ), you're essentially saying the rate should be better than 11.44%? Which is in effect what I said. How much better than 11.44 is the question? any suggestions? Regardless, both are a lot better than 15%.