Sumwise

Percentage Change from 28 to 21

From 28 to 21 is a 25% decrease

Change
-25%
Difference
-7
New ÷ old
0.75
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: 21 − 28 = -7
  2. Divide by the starting value: -7 ÷ 28 = -0.25
  3. Multiply by 100: -25%
  4. Check: Work forwards from the start: 28 × (1 − 0.25) = 28 × 0.75 = 21.

In a spreadsheet: =(21-28)/28*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 75% of the old one: for every 100 at the start there are now 75, so 25 out of every 100 have gone.

Sales: a price cut from $28 to $21 is a 25% discount.

Why the change back is different

A 25% fall followed by a 25% rise does not bring you back to 28: it gives 26.25. The second percentage is taken of 21, not of 28, so to undo this change you need 33.3333% instead.

Related results

Results for nearby numbers
28 to 19

From 28 to 19 is a 32.1429% decrease

28 to 20

From 28 to 20 is a 28.5714% decrease

28 to 22

From 28 to 22 is a 21.4286% decrease

28 to 23

From 28 to 23 is a 17.8571% decrease

28 to 31

From 28 to 31 is a 10.7143% increase

The other way round: Percentage change from 21 to 28. Percentage change is not symmetric: from 28 to 21 is -25%, but from 21 back to 28 is 33.3333%, because the starting value is the base. For a comparison that is the same both ways, use the percentage difference between 21 and 28: 28.5714%. See Percentage difference between 21 and 28.

Practice

6 to 99
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From 6 to 99 is a 1,550% increase

16 to 4
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From 16 to 4 is a 75% decrease

22 to 52
Show answer

From 22 to 52 is a 136.3636% increase

19 to 16
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From 19 to 16 is a 15.7895% decrease

26 to 27
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From 26 to 27 is a 3.8462% increase

28 to 47
Show answer

From 28 to 47 is a 67.8571% increase

Calculate another

How answers are calculated and checked: methodology.

Questions

Percentage Change from 28 to 21

Going from 28 to 21 is a 25% decrease. Formula and steps.

Is going from 28 to 21 an increase or a decrease?

A decrease: the value fell by 7, which is 25% of the starting value.

What is the percentage change from 21 back to 28?

33.3333%. It is a different number because the starting value is now 21, not 28.