I have dozens of such loans at 2/3/4/5% rates and 60 days, made by my bot so no big amount for each. I had about 10BTC on Poloniex to lend at the end of July and since then 2 thirds have closed early, I expect the remaining BTC to last a few days still.

7BTC earned for you, congrats !

I have another one from early July at 0.135% so about 50% annual after Polo takes its share, this one has been going on one month.

Rates at the moment are crazy low though.