What is the Percentage Difference from 40 to 29?
From 40 to 29 is a 27.5% decrease
Step by step
- Difference: 29 − 40 = -11
- Divide by the starting value: -11 ÷ 40 = -0.275
- Multiply by 100: -27.5%
How the answer is worked out
Percentage change measures a difference against the value you started with. The value went from 40 to 29, a difference of 11. Compared with the starting value of 40, that difference is 27.5%, so this is a 27.5% decrease.
The new value is 72.5% of the old one: for every 100 at the start there are now 72.5, so 27.5 out of every 100 have gone.
Why calculate this?
Percentage change compares a new value with an old one regardless of size: price rises, growth, discounts, score changes.
- Sales: a price cut from $40 to $29 is a 27.5% discount.
- Weight: going from 40 to 29 kilograms is a loss of 27.5% of the starting weight.
- Results: if a team scores 29 points this season after 40 last season, its total has dropped by 27.5%.
A quicker way
Find 1% of the starting value: 40 ÷ 100 = 0.4. The difference of 11 is 27.5 of those steps.
Percentage change is not the same as percentage points. If a rate moves from 40% to 29%, it changes by 11 percentage points, but by 27.5% relative to where it started.
Check the answer
Work forwards from the start: 40 × (1 − 0.275) = 40 × 0.725 = 29. Getting 29 shows the answer is right.
Rounding
Rounded to a whole number the change is -28, to one decimal place -27.5 and to two decimal places -27.50. Round only at the end: rounding halfway through a calculation can change the last digit.
The formula explained
percentage change = (new value − old value) ÷ old value × 100. A positive result is an increase and a negative result is a decrease. The old value is always the base, which is why the change from A to B and from B to A are different percentages.
Another worked example: 8 to 95
- Difference: 95 − 8 = 87
- Divide by the starting value: 87 ÷ 8 = 10.875
- Multiply by 100: 1,087.5%
Why the change back is different
A 27.5% fall followed by a 27.5% rise does not bring you back to 40: it gives 36.975. The second percentage is taken of 29, not of 40, so to undo this change you need 37.931% instead.
Other ways to ask this
The same calculation is often asked in other words. All of these have the answer above:
- Percentage decrease from 40 to 29
- What percent less is 29 than 40?
- 40 to 29 as a percent change
- How much did 40 fall going to 29, in percent?
- Relative change between 40 and 29
Terms used on this page
- Old value: the starting amount, used as the base of the percentage.
- New value: the amount after the change.
- Increase: a positive change: the new value is bigger.
- Percentage point: the plain difference between two rates, not a relative change.
The answer in other forms
| Change | -27.5% |
|---|---|
| Difference | -11 |
| New ÷ old | 0.725 |
| Direction | decrease |
Related results
| 40 to 27 | From 40 to 27 is a 32.5% decrease |
| 40 to 28 | From 40 to 28 is a 30% decrease |
| 40 to 30 | From 40 to 30 is a 25% decrease |
| 40 to 31 | From 40 to 31 is a 22.5% decrease |
| 40 to 39 | From 40 to 39 is a 2.5% decrease |
The other way round: Percentage difference from 29 to 40
Doing it in a spreadsheet
In Excel, Google Sheets or Numbers type =(29-40)/40*100 into any cell. Replace the numbers with cell references (for example A1 and B1) to reuse the formula for a whole column.
Common mistakes
Always divide by the starting value, not the new one. A rise from 40 to 50 is +25%, but the fall from 50 back to 40 is −20%.
Practice examples
| 8 to 95 | Show answerFrom 8 to 95 is a 1,087.5% increase |
| 61 to 28 | Show answerFrom 61 to 28 is a 54.0984% decrease |
| 49 to 76 | Show answerFrom 49 to 76 is a 55.102% increase |
| 96 to 58 | Show answerFrom 96 to 58 is a 39.5833% decrease |
| 86 to 76 | Show answerFrom 86 to 76 is a 11.6279% decrease |
| 29 to 46 | Show answerFrom 29 to 46 is a 58.6207% increase |
| 24 to 81 | Show answerFrom 24 to 81 is a 237.5% increase |
| 56 to 31 | Show answerFrom 56 to 31 is a 44.6429% decrease |
| 50 to 53 | Show answerFrom 50 to 53 is a 6% increase |
| 42 to 19 | Show answerFrom 42 to 19 is a 54.7619% decrease |
How this answer was calculated
The result is worked out from the numbers in this page's address when the page is opened, using exact arithmetic wherever possible and rounding only for display. Nothing is copied from a printed table. If you think an answer is wrong, please tell us through the contact page and we will check it.
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Questions
What is the Percentage Difference from 40 to 29?
Going from 40 to 29 is a 27.5% decrease. Formula and steps.
Is going from 40 to 29 an increase or a decrease?
A decrease: the value fell by 11, which is 27.5% of the starting value.
What is the percentage change from 29 back to 40?
37.931%. It is a different number because the starting value is now 29, not 40.
What is the percentage difference between 40 and 29?
When neither value is the starting point, use the average as the base: 11 ÷ 34.5 × 100 = 31.8841%. That is the symmetric percentage difference.
How do I calculate percentage change in Excel or Google Sheets?
Put the old value in A1 and the new value in B1, then type =(B1-A1)/A1 and format the cell as a percentage. For these numbers it shows -27.5%.