garfieldthecat

It is very easy to build your own XIRR function. This stackoverflow answer is a good example: https://stackoverflow.com/a/66069439/4045275 If instead you have very specific needs with respect to day count...

Sure, do let me know. A couple of comments: 1. part of the reason why all the functions are very slow seems to be the fact that they are set...

@kigawas You are wrong. You are not the first one to make this error, but it remains an error. If you take a 100 loan (I am intentionally ignoring the...

Well, to be fair, the formula is not calculus - it is basic algebra (just fractions and powers), of the kind which tends to be taught between the ages of...

I don't follow - you can't agree on what? And why? Critical thinking? What do you mean?

In your example, are the periods monthly, annual or what? Your formula would be correct for a 300-year loan charging 14.79% per year - but I can't think of many...

I asked because, in my experience, it is a relatively common mistake (see eg this other issue https://www.iso.org/iso-8601-date-and-time-format.html ). Wow, almost 15% per week! 769% per year!!! May I ask...

Practical advice, if I may: it will probably be easier and faster not to use ppmt and ipmt, but to use only pmt() to calculate the total instalment, then calculate...

@geoffwright240 very good catch! Also worth following https://quant.stackexchange.com/questions/63877/future-value-the-functions-in-excel-and-numpy-financial-dont-work-when-number ; Excel has the same behaviour, too

I think the title and the discussion fail to make explicit the enormity of the issue that, **in pandas, a column can contain dates formatted in different ways, so that...