Bondora Interest Payments Calculation

Hello

I am trying to understand and replicate the interest calculation of Bondora.

Unfortunately are my tries unsuccessful.

Here I will describe what I have done so far. And you can find my calculation under the following link

drive.google.com/open?id=1yPEqG1lXYk2yzlVRlPJA8rqFE8E9Q2XtikfBiOyEsKo

I downloaded the loan information from the both files LoanData.csv and FutureCashflows.csv .

And you can see that the annual interest rate should be 37.99%

Using the given principal payments I can easily calculate the remaining part of the principal (Column K). If I then divide the provided absolute interest payment by the remaining principal I should come to the used percentage interest rate for the relevant period (Column L).

Here is exactly the problem. I am not able to find out how Bondora calculates these interest rates. I tried couple of different methods but unfortunately all of them come to slightly different numbers than the interest rates which Bondora seems to use. You can see my tries in the Columns N-P

• (Column N) Equally distributed over the 12 months interest of 1/12 of the given annual rate
• (Column O) Rate which is proportional to number days in the corresponding month
• (Column P) Rate which is proportional to number days between the payments schedule is little different that calendar months

Is someone from you able to reproduce the Bondora calculation for the interest?

Thanks you very much in advance

Mopcku