Finance on Ask Eijaz

Excel 365: Build a Loan Amortization Schedule in One Formula (No Helper Columns)

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

Okay, real talk: almost every loan amortization schedule in the wild is held together with hope. You type PMT once, work out the interest and principal for row one, then drag the whole thing down 360 rows and call it a mortgage. It looks authoritative. It even reconciles to the penny — right up until someone inserts a row to add a note, changes the term from 30 years to 15, or refinances halfway through, and the entire ladder quietly comes apart at the seams.

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.

Tiered Commission Formulas in Excel 365: Why VLOOKUP Gets It Wrong

Mon, 17 Aug 2026 00:00:00 +0000

Okay, real talk: if you’ve ever built a commission plan, a bulk-discount schedule or a tax provision in Excel, you’ve probably written this exact formula — a VLOOKUP against a tier table. It looks confident. It returns a nice, clean number. And that number is quietly, cheerfully wrong, because it slaps one rate on the entire amount instead of giving each slice of it the rate it actually earned. Sales ops, RevOps and finance folks run into this all the time and don’t even notice, because the formula never errors out — it just over- or underpays and smiles about it.