Sumwise

Percentage Change from 31 to 18

From 31 to 18 is a 41.9355% decrease

Change
-41.9355%
Difference
-13
New ÷ old
0.580645
Direction
decrease

Sumwise · Maintained by Theo Abbott (pen name) · automated checks · Data: exact arithmetic; unit definitions from NIST SP 811 · Updated · How the checks work

How to work it out

  1. Difference: 18 − 31 = -13
  2. Divide by the starting value: -13 ÷ 31 = -0.419355
  3. Multiply by 100: -41.9355%
  4. Check: Work forwards from the start: 31 × (1 − 0.419355) = 31 × 0.580645 = 18.

In a spreadsheet: =(18-31)/31*100. 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%.

What the result means

The new value is 58.0645% of the old one: for every 100 at the start there are now 58.0645, so 41.9355 out of every 100 have gone.

Sales: a price cut from $31 to $18 is a 41.9355% discount.

Why the change back is different

A 41.9355% fall followed by a 41.9355% rise does not bring you back to 31: it gives 25.5484. The second percentage is taken of 18, not of 31, so to undo this change you need 72.2222% instead.

Related results

Results for nearby numbers
31 to 16

From 31 to 16 is a 48.3871% decrease

31 to 17

From 31 to 17 is a 45.1613% decrease

31 to 19

From 31 to 19 is a 38.7097% decrease

31 to 20

From 31 to 20 is a 35.4839% decrease

31 to 28

From 31 to 28 is a 9.6774% decrease

The other way round: Percentage change from 18 to 31. Percentage change is not symmetric: from 31 to 18 is -41.9355%, but from 18 back to 31 is 72.2222%, because the starting value is the base. For a comparison that is the same both ways, use the percentage difference between 18 and 31: 53.0612%. See Percentage difference between 18 and 31.

Practice

6 to 33
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From 6 to 33 is a 450% increase

37 to 65
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From 37 to 65 is a 75.6757% increase

53 to 24
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From 53 to 24 is a 54.717% decrease

73 to 41
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From 73 to 41 is a 43.8356% decrease

98 to 68
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From 98 to 68 is a 30.6122% decrease

71 to 94
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From 71 to 94 is a 32.3944% increase

Calculate another

How answers are calculated and checked: methodology.

Questions

Percentage Change from 31 to 18

Going from 31 to 18 is a 41.9355% decrease. Formula and steps.

Is going from 31 to 18 an increase or a decrease?

A decrease: the value fell by 13, which is 41.9355% of the starting value.

What is the percentage change from 18 back to 31?

72.2222%. It is a different number because the starting value is now 18, not 31.