It’s really nice when comparing quotes for buying down a rate, or looking at the impact of additional payments. It’s also incredibly easy to throw together. For anyone interested:
payment = PMT(mortage rate/12, mortgage term * 12, -initial principle)
new principle = prev principle - principle payment
Throw that into a spreadsheet and drag down. Add a SUM() to figure out total interest paid or whatever. I have a VLOOKUP() to calculate interest for the current year for tax planning purposes, for example.
Maybe I’ll start an unofficial weekly post about various calculations I have in my spreadsheet. I have something like 30 tabs, so surely something there is interesting to others.
It’s really nice when comparing quotes for buying down a rate, or looking at the impact of additional payments. It’s also incredibly easy to throw together. For anyone interested:
PMT(mortage rate/12, mortgage term * 12, -initial principle)
(mortgage rate/12) * remaining principle
payment - interest
prev principle - principle payment
Throw that into a spreadsheet and drag down. Add a
SUM()
to figure out total interest paid or whatever. I have aVLOOKUP()
to calculate interest for the current year for tax planning purposes, for example.Maybe I’ll start an unofficial weekly post about various calculations I have in my spreadsheet. I have something like 30 tabs, so surely something there is interesting to others.