Excel 365: Why Your NPV Is Wrong (and the XNPV Fix Analysts Swear By)

Wed, 19 Aug 2026 00:00:00 +0000

Okay, real talk: =NPV(rate, values) is one of the most confidently wrong formulas in corporate finance. You select your cash flows, type the function, get a clean dollar figure, drop it in the board deck — and you’ve just discounted your entire project by one period too many. Excel’s NPV assumes the first number in your range arrives one full period from today, not today. Feed it your day-one capital outlay and it dutifully discounts money you’re spending right now as if it happens next year. The result is off by thousands, and it never once shows an error.

Irr on Ask Eijaz

Excel 365: Why Your NPV Is Wrong (and the XNPV Fix Analysts Swear By)