I have got some ETH that I could lend but I personnaly don't find the rates interesting against the risk of lending. For the moment, lending around 200 days would only get you around 2%... So why are you lending ??

It looks like you've used a simple-interest calculation. Try this algo:
Annual Rate = (1 + daily rate)^365 - 1
Eg: Annual Rate = (1.0002)^365 - 1 = 1.0757- 1 = 7.57%.
So...if you can snag 0.02% per day, day after day, you'd make 7.57% over a year.
https://en.wikipedia.org/wiki/Compound_interest