I was skeptical about the Average Annual Return and IRR calculations on the Investment tab of Quicken for Windows mainly because the documentation didn't make any sense to me. It looked like someone cut and pasted it from a finance book without looking at the code or explaining the variables.
So I checked results on Mathematica, which is more clearly documented. I used Cisco over a five-year period ending 12/28/2021 (today). So it's a straightforward example. You buy some Cisco shares on 12/28/2016 collect the dividends for five years and sell the shares on 12/28/21. What's the value of that cashflow?
For Cisco stock my Quicken (Ver R37.62, Build 27.1.37.62) Investing tab shows, "Average Annual Return (%) 5-Year" = 13.5 and "ROI (%) 5-Year" = 82.3. But Mathematica shows the effective rate of return is 0.195499 or just under 20 percent.
I tried to attach the Mathematica notebook, but this web site wouldn't allow that. So it's published at
https://www.wolframcloud.com/obj/jgourle2/Published/cisco example.nb. That way you don't have to have Mathematica installed to test the definitions. The web site will run it for you.
There is plenty of room for error in my calculation. So I did something wrong, please let me know. On the other hand, if my reasoning is correct, you should probably make note of it before basing an investment decision on Quicken's math. It would be fairly easy to turn the notebook into a single function that returns the effective rate of return on any listed stock.