1. What is a Percentage Increase and Decrease Calculator?

Definition: This calculator determines the percentage change between an old value and a new value.

Purpose: It helps analyze growth or reduction in various contexts like prices, quantities, measurements, and performance metrics.

2. How Does the Calculator Work?

The calculator uses the formula:

Where:

• New Value — The current or final measurement
• Old Value — The original or initial measurement

Explanation: The difference between values is divided by the original value to get relative change, then multiplied by 100 to convert to percentage.

3. Importance of Percentage Change Calculation

Details: Percentage change provides a standardized way to compare changes across different scales and magnitudes.

4. Using the Calculator

Tips: Enter both old and new values. The calculator will show percentage increase (positive result) or decrease (negative result).

5. Frequently Asked Questions (FAQ)

Q1: What does a negative percentage mean?
A: A negative percentage indicates a decrease from the old value to the new value.

Q2: Can I calculate percentage change from zero?
A: No, percentage change is undefined when the old value is zero (division by zero).

Q3: How is this different from percentage difference?
A: Percentage change compares two values over time, while percentage difference compares two simultaneous values.

Q4: What's considered a significant percentage change?
A: Significance depends on context - a 5% price increase might be significant, while 5% population growth might not be.

Q5: How do I reverse a percentage change?
A: To return to original value after x% increase, decrease by (x/(100+x))×100%.