Comment by usrme

These are awesome and exactly the kind of formulas I wish I would have been taught earlier on my life! I've personally been using a free spreadsheet-based tool called the Investment Portfolio Tracker by The Measure of a Plan (https://themeasureofaplan.com/investment-portfolio-tracker/) and it's been absolutely wonderful; it never ceases to amaze me how much power spreadsheets have. The author has other tools as well (https://themeasureofaplan.com/tools/) and is really responsive via email. Be sure to donate if you find value in his work as I did!