I would like to add to the wish list a function for calculating the internal rate of return. This function is found in Excel and Apple Numbers.
Thank you.
I’ve just done some research into this and this is not a trivial task, though probably not a massive one either. I’ve added it to the issue tracker for possible future inclusion.
If I can get the IRR function included in Panorama, I may be able to shift my analytical work from Excel and Numbers to Panorama. The build-in charting, summary tables, and pivot tables are a big plus for PanoramaX
James
I’m on holidays at the moment but when I get home (next Wednesday), I’ll look into whipping up a procedure for you.
Jim, your BitBucket entry implies that there is not yet a Panorama X function for calculating Net Present Value. There is - the pv( function, carried over from P6.
The Bitbucket entry is regarding Net Present Value which is different from Present Value. Don’t ask me to explain it all until someone explains it to me. 
The internal rate of return is the value of r so that the summation below equals zero. Or to put it another way, the value of r for which the initial investment equals the sum of the present value of the payments received as a result of the investment.
For more information, see IRR.
I’ve written three procedures:
NPV with a constant cash flow
NPV with a variable cash flow
IRR with a constant cash flow
When I get home from holidays I’ll send these to James for his comments and then post them on Dropbox or the Database Exchange.
Hey guys, thanks for giving some thought to the IRR function. For it to be useful, we need to evaluation uneven cashflows. Thanks in advance for putting your genius brains to work on this.
I have an IRR for varying cashflows - I’m just putting the final polish on it.
Did I ever get around to posting this anywhere? Is it still needed?
Just in case, it can now be downloaded. Tom Cooper has helped significantly with the debugging but further feedback is welcome. Get it here:
Thank you, Michael.
Thanks, guys. I will take a look and test this against my Excel and Numbers templates.
Let me know how your tests of this go. If it seems appropriate I will consider adding it to Panorama X directly.
Please note that you can have multiple IRRs; one for each time the cash flow sign changes over time. For example, if the cash flow starts in say period 1 as a positive number and then changes to a negative number in say period 3 and then changes to a positive number in say period 6, you will have two IRRs; one for each change from positive to negative or vice versa in the sign of the cash flow.
However, Jim if you create a function for IRR will you also please create the “sister” function of Modified IRR (i.e. MIRR). MIRR uses two discount rates, whereas IRR uses one discount rate. The second discount rate in MIRR is for a future rate of growth.
Michael, Can you send me a new link to your IRR test formula? Thanks.
Here it is: