The formula used throughout:
(Vf − Vi) / Vi × 100 = percentage change
1. Salary raise
Your annual salary goes from $52,000 to $56,160. What is the percentage increase?Step 1 — identify the values: Vi = 52,000 Vf = 56,160
Step 2 — apply the formula: (56,160 − 52,000) / 52,000 × 100 = 4,160 / 52,000 × 100 = 8
Step 3 — interpret: Your salary increased by **8%**.
2. Population growth
A town’s population grows from 18,400 to 19,872 residents over one year. What is the percentage growth?Step 1: Vi = 18,400 Vf = 19,872
Step 2: (19,872 − 18,400) / 18,400 × 100 = 1,472 / 18,400 × 100 = 8
Step 3: The population grew by **8%** over the year.
3. Exam score change
A student scored 68 out of 100 on the first test and 59 out of 100 on the second. What is the percentage change in score?Step 1: Vi = 68 Vf = 59
Step 2: (59 − 68) / 68 × 100 = −9 / 68 × 100 = −13.24
Step 3: The score declined by **13.24%**. The negative sign shows a decrease.
4. Fuel price
The price of a gallon of gas rises from $3.10 to $3.42. What is the percentage increase?Step 1: Vi = 3.10 Vf = 3.42
Step 2: (3.42 − 3.10) / 3.10 × 100 = 0.32 / 3.10 × 100 = 10.32
Step 3: Gas prices rose by **10.32%**.
Want the theory behind these steps? Read the percentage change formula explained, or plug in your own numbers with the percentage change calculator.