At this very moment on CMC:
1 Bts = 0.027473 USD = A
According to the DEX's fake and corrupt and greedy price-feed:
1 Bts = 1/price-feed = 1/28.98551 = 0.0345 = B
So, the percent difference is:
100 x (B-A)/A = 25.6 % !!!!
Now, tell me where did you get your 9%