1. What Is Percentage Change?

Percentage change measures the degree of change over time. It's commonly used in finance, economics, statistics, and other fields to compare how a quantity has changed relative to its original value.

2. How The Calculation Works

The calculator uses the percentage change formula:

Where:

• \( \text{new} \) — The new or current value
• \( \text{old} \) — The original or old value

Key Points: A positive result indicates an increase, while a negative result indicates a decrease. The calculation is undefined when the old value is zero.

3. Practical Applications

Common Uses: Tracking stock price changes, measuring growth rates, analyzing sales performance, comparing experimental results, and assessing inflation rates.

4. Using The Calculator

Instructions: Enter the old (original) value and the new value. The calculator will compute the percentage change between them. Note that the old value cannot be zero.

5. Frequently Asked Questions (FAQ)

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

Q2: How is percentage change different from percentage difference?
A: Percentage change compares two values over time (sequential), while percentage difference compares two simultaneous values.

Q3: Why can't the old value be zero?
A: Division by zero is mathematically undefined, making percentage change calculation impossible when the old value is zero.

Q4: What's considered a significant percentage change?
A: Significance depends on context. In finance, even 1% might be significant, while in other fields, larger changes might be needed for importance.

Q5: How do I interpret a percentage change from 50 to 75?
A: This would be a 50% increase ((75-50)/50 × 100 = 50%).