Check out bfxdata, as of lately returns in BTC are about as high as in USD percentage wise.
They are actually higher. I bought BTC to lend them for that reason.
I have some BTC borrowed for LTC/BTC short; it turns out the borrowing rate is at least 0.5% a day, which translates to 600% a year...
I checked the USD rate at one brokerage and they asked for 7% a year... Bitcoin truly lives in the dark, dark ages.
EDIT: oops, no, it is just unclear if your fees are in USD, BTC or LTC... it was most likely LTC, not BTC.