The value fell from 60 to 8, a decrease of 86.67%.
Percentage decrease is the size of a drop between two values, expressed as a percentage of the value you started from, sometimes called the baseline or starting value. It is the standard way to describe a fall in price, revenue, population, weight or any other measured quantity, because stating the change as a proportion of the starting point makes drops of different absolute sizes directly comparable.
Every calculation has exactly three components. The original value is where the quantity started and always forms the denominator. The new value is where it ended up. The resulting percentage is the difference between them measured against that original value. Because the original value is the reference point, the same absolute drop produces a different percentage depending on where it began, a fall of 10 is a 10% decrease from 100, but a 50% decrease from 20.
The calculation takes four steps, and the order matters: the subtraction comes first, the division is always by the original value, and the sign of the answer is what tells you which direction the quantity actually moved.
Working through 250 falling to 200: the difference is 50, dividing by 250 gives 0.2, multiplying by 100 gives 20, and the result is positive, so 250 to 200 is a 20% decrease. Keep the units of the two values identical before you start, comparing a figure in thousands against one in millions is the fastest way to be out by a factor of a thousand. If either value is a percentage itself, decide first whether you want a percentage decrease or a change in percentage points, because those are different questions with different answers.
The formula is a ratio before it is a percentage. Subtracting the new value from the original gives the size of the drop in original units; dividing by the original value rescales that drop so it is expressed relative to where the quantity started, which is what makes the result comparable across quantities of any size. Multiplying by 100 only converts the ratio into percentage notation, it adds no information.
The absolute value in the denominator exists to protect the sign. The numerator alone already encodes direction: it is positive when the value fell and negative when it rose. If the denominator were allowed to be negative too, the two minus signs would cancel and a genuine increase would be reported as a decrease. Forcing the denominator positive means the sign of the answer always comes from the numerator, so a positive result reliably means a decrease no matter where on the number line the values sit.
Both examples below use the same four steps, on values that differ by five orders of magnitude, which is the point of working in percentages at all.
The pairs below are the ones people look up most often, each calculated with the same formula and rounded to one decimal place where the result does not land exactly.
| Original Value | New Value | Percentage Decrease |
|---|---|---|
| 100 | 10 | 90% |
| 5,000 | 1,000 | 80% |
| 750 | 590 | 21.3% |
| 80 | 60 | 25% |
| 5 | 3 | 40% |
Percentage increase divides the rise by the original value, while percentage decrease divides the fall by it. Because the denominator is always the starting number, the two are not symmetrical: a 50% decrease from 100 gives 50, but returning from 50 to 100 is a 100% increase. Reversing a decrease always takes a larger percentage than the one that created it.
Percentage change is the umbrella term that covers both directions with one signed formula. Percentage decrease is the case where the result comes out positive under the decrease convention, or negative under the change convention. If you do not know in advance whether a value rose or fell, calculate percentage change and read the sign.
Percentage difference compares two values that have no natural before and after, so it divides by their average rather than by one of them. That makes it symmetrical: comparing 40 and 60 gives 40% whichever order you use. Percentage decrease is directional and needs a defined starting point.
Percentage points measure the gap between two figures that are already percentages, by plain subtraction. Moving from 40% to 30% is a 10 percentage point drop, but it is a 25% decrease, because 10 divided by 40 is 0.25. Mixing the two units is the single most common error in reporting rates.
A percentage decrease connects three quantities, the original value, the new value and the rate, so knowing any two of them gives you the third. The calculator at the top of this page solves for the rate. The two formulas below solve for the other two directions.
A jacket marked down 30% to $84 started at 84 ÷ 0.70 = $120, not at $109.20. Adding 30% back to the sale price gives the wrong answer, because that would take 30% of the smaller number. The reverse formula breaks down only at a 100% decrease, where the divisor becomes zero and the original value is unrecoverable. For the dedicated tool with both directions built in, see the reverse percentage calculator.
Put the original value in column A and the new value in column B, then enter this formula. It is identical in Excel and Google Sheets, since both share the same ABS function and operator precedence:
| Row | A | B | C |
|---|---|---|---|
| 1 | 60 | 8 | 86.67 |
| 2 | 1000 | 750 | 25.00 |
| 3 | 5000 | 1000 | 80.00 |
Fill the formula down to cover as many pairs as you need. The *100 is only there so the cell reads 86.67 rather than 0.8667, drop it and format the column as a percentage instead if you prefer the percent sign applied automatically.
Each cell shows what remains of the row's base value after the column's decrease is applied. Read across to compare rates on one base, or down to see the same rate at a different scale.
| Base value | −5% | −10% | −15% | −20% | −25% | −30% | −50% | −75% |
|---|---|---|---|---|---|---|---|---|
| 10 | 9.5 | 9 | 8.5 | 8 | 7.5 | 7 | 5 | 2.5 |
| 50 | 47.5 | 45 | 42.5 | 40 | 37.5 | 35 | 25 | 12.5 |
| 100 | 95 | 90 | 85 | 80 | 75 | 70 | 50 | 25 |
| 500 | 475 | 450 | 425 | 400 | 375 | 350 | 250 | 125 |
| 1,000 | 950 | 900 | 850 | 800 | 750 | 700 | 500 | 250 |
| 5,000 | 4,750 | 4,500 | 4,250 | 4,000 | 3,750 | 3,500 | 2,500 | 1,250 |
Scroll the table sideways to see every rate.
A price tag cut from $80 to $60 is a 25% decrease, which is exactly what a 25% off sticker promises. Shoppers use the calculation in reverse to check whether the advertised percentage drop matches the shelf price, and to compare two offers written in different formats, a flat amount off against a percentage off.
Finance teams report revenue, margin and headcount movements as percentage reductions so that periods of different sizes stay comparable. A $250,000 fall means little on its own; describing it as a 25% decline against a $1,000,000 base makes it immediately legible next to any other quarter.
Drawdowns, corrections and bear markets are all defined by percentage decrease from a peak. A 20% fall from a high is the conventional threshold for a bear market. Because the denominator is the peak, recovering a 20% loss requires a 25% gain, the asymmetry that makes large losses so expensive.
Statistical agencies express shrinking populations, birth rates and school enrolments as annual percentage decreases. Expressing the change as a rate rather than a headcount lets a small town and a large city be compared on the same scale, and lets a decline be projected forward.
Clinical guidance is usually written in percentage terms, a 5% to 10% reduction in body weight, for instance, because the same percentage represents a comparable effort and a comparable health benefit at any starting weight. Blood pressure, cholesterol and resting heart rate reductions are reported the same way.
Laboratories report reductions in concentration, mass, absorbance and reaction rate as percentage decreases, which keeps results comparable between runs that used different sample sizes. The same measure appears in error analysis, efficiency losses and any before-and-after experimental comparison.
A population decline rate is this same formula applied to headcounts over time: subtract the later population from the earlier one, divide by the earlier figure, and multiply by 100. Because the result is a rate rather than a raw number of people, a village and a metropolis can be placed on the same axis.
The United States and India both sit on the rising line: their totals keep climbing year on year, so the formula returns a negative decrease, which is read as growth. Japan sits on the declining line, with a population that has been shrinking for well over a decade, producing a small positive decrease each year. Those annual rates look modest in isolation, a fraction of a percent, but they compound, which is why demographers report the rate rather than the headcount. A sustained 0.5% annual percentage decline removes roughly 5% of a population in a decade.
A negative result is not an error: it means the new value is larger than the original, so the quantity increased. The formula measures signed movement, and it is the numerator that carries the direction. The calculator above flags this in words rather than showing a minus sign you might miss.
When the original value is positive, a decrease falls naturally between 0% and 100%: 0% means nothing changed, and 100% means the value reached zero. Only a fall past zero into negative territory can exceed 100%, as with a profit of $500 becoming a loss of $100, a 120% decrease. Two further cases need care. An original value of zero has no valid answer at all, because the formula would divide by zero. And when the original value is itself negative, the absolute value in the denominator keeps the sign honest, so moving from −200 to −250 is correctly a 25% decrease.
=(A1-B1)/ABS(A1) and format the cell as Percentage, so Excel adds the percent sign and scales the number for you. Fill the formula down a column to compare hundreds of pairs at once, and wrap it in IFERROR if any original value might be blank or zero.