Geek Stuff How to calculate an internal rate of return (IRR), and when not to use it | Experiments in Finance March 4, 2008 Jack How to calculate an internal rate of return (IRR), and when not to use it | Experiments in Finance Very Interesting. Share this:Share Share on Facebook (Opens in new window) Facebook Print (Opens in new window) Print Email a link to a friend (Opens in new window) Email