Percentage Increase & Decrease Formula

Mathematics & Education Formula • Published on July 30, 2026 • Last updated July 30, 2026

Mathematical Equation

$$\text{Percentage Change (\%)} = \frac{\text{New Value} - \text{Initial Value}}{|\text{Initial Value}|} \times 100$$

Variable Definitions

Initial Value

Starting baseline quantity

New Value

Final resulting quantity

Detailed Explanation

In-Depth Guide

The percentage change formula measures relative growth (increase) or decline (decrease) between an initial value and a final value as a percentage of the original number.

How to Calculate: Step-by-Step

1. Subtract initial value from new value to find absolute difference. 2. Divide absolute difference by initial baseline value. 3. Multiply quotient by 100 to convert to percentage.

Worked Calculation Example

Price increases from $50 to $65: - Difference = 65 - 50 = 15. - Change = (15 / 50) × 100 = 30% increase.

Common Use Cases

  • Salary appraisal calculations
  • Inflation & price hike metrics
  • Sales growth analysis

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