I don't agree with the philosophy that you don't lose the money until you sell. Regardless of whether an investment is up or down, the only thing that matters is your assessment of the future.
If my buggy whip stock is down 75%, it might be time to acknowledge that buggy whips aren't a growth industry and accept my loss. When my Exxon stock was down, I believed that oil would continue to be a critical resource for the world, and I rode it out.
When I retired, I started paying closer attention to my investments, and I learned that several of the financial terms don't mean what I intuitively think they should mean.
To me, "amount invested" means the money that I took from my wallet and placed into an investment. If that investment produced dividends, which I allow to reinvest, my wallet would say that those dividends are part of the investment return. Financial software says those dividends add to my "amount invested". This causes the calculated "return" and "% return" to be lower than I would expect.
When evaluating long-term performance, it is also critical to "show closed lots". This means that, even if you sell a bad investment, it will still show up on your portfolio report with a current value of zero, and it is still used in the overall performance stats for the portfolio. This can make a HUGE difference in the calculated return and % return.
Internal rate of return (IRR) is the value that makes the most sense to me. It takes into account all of the buys and sells and dividends, and it calculates the equivalent annual interest rate that would generate the resulting value over time. IME, the IRR is unaffected by the "show closed lots" setting.
I also find that the RATE of return (IRR) is much more useful than the % return. If I have an investment that has generated a 30% return, that might be great, or it might be lousy. If I've only had it for a year, that's great. If I've had it for 20 years, then that's not so good.
