...an adjusted net annualized return of 21.59% with a weighted average interest rate of 19.92% with 1341 loans

So, what you are saying is that the interest rate is 19.92% but you are somehow earning 21.59%.

Perhaps my understanding of what those numbers mean is wrong?

If you look at the attachment I provides from LC website on previous post, it is not what I say but as per LC website when they analyzes the portfolio performance. When I do my own ROR calculation I get numbers close to LC and my return is higher than the weighted average of my account.

I guess it is due to the fact that I buy some notes and sell them after a month or two at a 7.0% premium or so.

For example I purchase 2 Loans (see attached) at 25 dollars paying 19.99% interest rate and after they

made one payment their credit score went from 720 to 815. This is a good indication that the borrower took the funds and close his/her cc debt and caused the credit score to shot up fast! This note should sell at a high premium now since it is very low risk given the interest rate of 19.99%) I was able to sell them at 26.64 so the

annual return on these 2 notes ((26.64+.61)*.99)^(365/45) -1 = 185% (the period return is 7.91% (26.64+.61)*.99/25 but I was able to get it in 45 days) It took me a long time to be able to better pick loans that are good candidates to behave so in the future. I am able to do it on a very low subset of my notes but it pushes the return higher than the effective weighted average and compensate me for selling notes in Grace Period at a loss.

I used to spend many hours looking at notes, risk profile, many pivot table experiments in excel etc... but now I am able to spend on average 30 min per day on LC no more, I guess some people think this is also too much.