Not a suggestion.

I am attempting this kata and is very confused by a few things

1. Is this a compound interest or simple interest, and how often is it recalcualted? (per year,month or day?)
2. There seem to have am inconsistency of how many days are there in a year? (in the example from 2016 jan 1 -> 2017 jan 1 is considered 366 days but in the interest rate bank considers 360 day a year)