How to Calculate Percentage Change in Excel

Percentage change is one of the most useful calculations in any spreadsheet — whether you're tracking sales figures month over month, comparing last year's budget to this year's, or analyzing how a stock price shifted. Excel makes this calculation straightforward once you understand the formula behind it, but there are a few variations worth knowing depending on what your data looks like.

The Core Formula for Percentage Change

The mathematical foundation is simple:

Percentage Change = (New Value − Old Value) / Old Value

In Excel, that translates directly into a formula. If your old value is in cell A2 and your new value is in cell B2, the formula would be:

=(B2-A2)/A2 

That gives you a decimal result. To display it as a percentage, format the cell as Percentage (either through the Home ribbon or by pressing Ctrl+Shift+%). Excel will multiply the decimal by 100 and add the % symbol automatically.

So if A2 is 200 and B2 is 250, the result is 0.25 — formatted as 25%. That's a 25% increase.

Handling Decrease vs. Increase

The same formula works for both increases and decreases. If B2 were 150 instead of 250:

=(150-200)/200 = -0.25 

Formatted as a percentage: -25%. A negative result means the value went down. Excel doesn't require a different formula — the sign handles the direction automatically.

Calculating Percentage Change Across a Column 📊

When you have a list of values and want to calculate the change between each consecutive row, the approach scales easily.

Say column A holds monthly revenue figures from A2 to A13 (January through December). In B3, you'd enter:

=(A3-A2)/A2 

Then drag that formula down through B13. Excel adjusts the row references automatically. Leave B2 blank — there's no previous value to compare January against.

Format the entire B column as Percentage and you now have a month-over-month percentage change column.

Using Absolute References for a Baseline Comparison

Sometimes you don't want consecutive comparisons — you want to compare every value against a single fixed baseline. For example, measuring how each month performs relative to January.

In that case, lock the baseline cell using an absolute reference with the dollar sign:

=(A3-$A$2)/$A$2 

The $A$2 stays fixed as you drag the formula down. A3, A4, A5 will update — but the denominator always points back to January's figure.

This approach is common in financial modeling, index tracking, and performance dashboards.

What Happens with Zero or Negative Values

This is where things get tricky. The percentage change formula breaks down in two situations:

For zero denominators, a common fix is wrapping the formula in IFERROR:

=IFERROR((B2-A2)/A2, "N/A") 

This replaces the error with a readable label rather than leaving a broken cell. For negative baselines, there's no single universal fix — how you handle it depends on what the data actually represents and how you need to interpret the result.

Displaying the Result Clearly

A few formatting tips that matter in practice:

• Decimal places: By default, Excel may show too many or too few. Use the increase/decrease decimal buttons in the Home ribbon to control precision. Two decimal places (e.g., 12.47%) is usually right for business reporting.
• Conditional formatting: You can color-code cells so positive changes appear green and negative changes appear red. This makes a long table scannable at a glance without reading every number.
• Custom number format: If you want to always show a + sign for positive values, apply the custom format +0.00%;-0.00% to the cell range.

Percentage Change vs. Percentage Difference ⚠️

These two terms sound similar but mean different things:

Percentage change implies a direction — there's a starting point (old) and an end point (new). Order matters.

Percentage difference is symmetric — it compares two values without treating either as the baseline. The formula is:

=ABS(A2-B2)/((A2+B2)/2) 

This is used when comparing two things that don't have a before/after relationship — like two products, two regions, or two test groups.

Using the wrong formula for your context will produce a valid-looking number that answers the wrong question.

Variables That Affect How You Set This Up

How you structure the calculation in Excel depends on several factors specific to your situation:

• Data layout — Are values in rows or columns? Consecutive or compared to a fixed point?
• Data type — Are you working with revenue, counts, temperatures, prices? Negative values or zeros change the approach.
• Purpose — Internal analysis, a client report, or a dashboard each have different formatting and readability needs.
• Excel version — Older versions of Excel handle some error functions slightly differently, though the core arithmetic hasn't changed.
• Volume — A 12-row monthly table and a 50,000-row dataset both use the same formula, but performance and structure considerations differ when working at scale.

The formula itself is consistent. What varies is how you handle edge cases, display the output, and connect it to the broader context of your spreadsheet — and that's entirely shaped by what you're actually trying to measure and who needs to read it.