You've been doing it the hard way, and you don't have to. The formula that user shared, twelve cell references multiplied together, raised to the one-third power, minus one, is correct in its logic but painful in practice. It's fragile, hard to audit, and a nightmare to extend if you want to add another quarter. The good news is that there's a cleaner path forward, and it doesn't require memorizing a wall of parentheses.
The core problem isn't the math; it's the method. Multiplying a chain of `(1+return)` values manually works, but it forces you to type every cell reference by hand. One misclick, one wrong row, and your annualized return is quietly wrong. A better approach uses Excel's `PRODUCT` function, which does the same multiplication in a single, readable formula: `=PRODUCT(1+M57:M68)^(1/3)-1`. That's it. The function handles the range, and you can adjust the number of quarters by simply changing the range reference. For a four-quarter average, swap the range to four cells and change the exponent to `1/1`. For eight quarters, it's `1/2`. The pattern stays consistent, and the formula stays short.
This matters because your investment tracking shouldn't be a source of anxiety every quarter. When you're manually building long formulas, you're spending mental energy on spreadsheet mechanics instead of on the actual returns. The `PRODUCT` method frees you to focus on what the numbers mean: whether your portfolio is meeting its goals, how recent quarters compare to longer trends, and where you might want to adjust. It also makes your spreadsheet easier to share or revisit months later, because you or anyone else can read the formula and immediately understand what it's doing.
The larger lesson here is that traditional spreadsheets often hide simpler solutions behind their own complexity. You don't need to memorize every function, but knowing a handful of them, `PRODUCT`, `GEOMEAN`, `XIRR` for irregular cash flows, can transform a quarterly chore into a quick, reliable check. Start with `PRODUCT` for your next calculation. It's one function, one range, and one exponent. That's all it takes to move from a formula that feels like a puzzle to one that feels like a tool.