Consider a CMBS with the following characteristics (Same as Questions 4, 5, and 6):

Backed by $20M mortgages, 7% interest, 5-yr maturity, IO annual payments, no servicer fee

There are three tranches issued:

-$13M Tranche A (Senior/Investment Grade CMBS) with coupon rate 5%

-$7M Tranche B (Junior/ Non-investment Grade CMBS) with coupon rate 6%-IO residual tranche (no extra collateral, but collects extra interest)

What is the subordination on this CMBS? (answer in %, e.g. for 5% enter 5)