Sumwise

Percentage Change from 30 to 40

From 30 to 40 is a 33.3333% increase

Change
33.3333%
Difference
10
New ÷ old
1.333333
Direction
increase

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: 40 − 30 = 10
  2. Divide by the starting value: 10 ÷ 30 = 0.333333
  3. Multiply by 100: 33.3333%
  4. Check: Work forwards from the start: 30 × (1 + 0.333333) = 30 × 1.333333 = 40.

In a spreadsheet: =(40-30)/30*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 1.3333 times the old one: for every 100 at the start there are now 133.3333.

Prices: an item whose price rises from $30 to $40 has gone up by 33.3333%.

Why the change back is different

A 33.3333% rise followed by a 33.3333% fall does not bring you back to 30: it gives 26.6667. The second percentage is taken of 40, not of 30, so to undo this change you need 25% instead.

Related results

Results for nearby numbers
30 to 38

From 30 to 38 is a 26.6667% increase

30 to 39

From 30 to 39 is a 30% increase

30 to 41

From 30 to 41 is a 36.6667% increase

30 to 42

From 30 to 42 is a 40% increase

30 to 50

From 30 to 50 is a 66.6667% increase

The other way round: Percentage change from 40 to 30. Percentage change is not symmetric: from 30 to 40 is 33.3333%, but from 40 back to 30 is -25%, because the starting value is the base. For a comparison that is the same both ways, use the percentage difference between 30 and 40: 28.5714%. See Percentage difference between 30 and 40.

Practice

6 to 22
Show answer

From 6 to 22 is a 266.6667% increase

67 to 18
Show answer

From 67 to 18 is a 73.1343% decrease

65 to 15
Show answer

From 65 to 15 is a 76.9231% decrease

62 to 42
Show answer

From 62 to 42 is a 32.2581% decrease

40 to 96
Show answer

From 40 to 96 is a 140% increase

15 to 57
Show answer

From 15 to 57 is a 280% increase

Calculate another

How answers are calculated and checked: methodology.

Questions

Percentage Change from 30 to 40

Going from 30 to 40 is a 33.3333% increase. Formula and steps.

Is going from 30 to 40 an increase or a decrease?

An increase: the value grew by 10, which is 33.3333% of the starting value.

What is the percentage change from 40 back to 30?

-25%. It is a different number because the starting value is now 40, not 30.