1. Calculating Percent Change
What is the percent change of:
to 50 Or
60 to 15?

2. Step 1: Find the change in value
When you calculate percent change You have to find the change in value
20 to 50
What is the difference between 20 and 50?

3. … change in value (cont.)
Subtract the old from the new one
Old to New
20 to 50
New – Old = Change in Value
50 – 20 = 30

4. Step 2: Divide Change in Value by Original Number
Then divide by the original
Change in Value Original Number 30 20 =

5. … Dividing (cont.)
Got a decimal answer number 30 20 =

6. Step 3: Convert to Percent
Converting to percent ain’t strange
1.5 = ??? %

7. … Convert to Percent (cont.)
By multiplying by a hundred
1.5 x 100 = ???

8. That’s Percent Change!
And that’s percent change!
1.5 x 100 = 150%

9. Step 1: Find the change in value
When you calculate percent change You have to find the change in value
60 to 15
What is the difference between 60 and 15?

10. … change in value (cont.)
Subtract the old from the new one
Old to New
60 to 15
New – Old = Change in Value
15 – 60 = -45

11. Step 2: Divide Change in Value by Original Number
Then divide by the original
Change in Value Original Number
-45 60 =

12. … Dividing (cont.)
Got a decimal answer number
-45 60 =

13. Step 3: Convert to Percent
Converting to percent ain’t strange
-.75 = ??? %

14. … Convert to Percent (cont.)
By multiplying by a hundred
-.75 x 100 = ???

15. That’s Percent Change!
And that’s percent change!
-.75 x 100 = -75%