1. What is Percentage Change?

Percentage change measures the degree of change over time, expressed as a percentage. It's used to compare how much a quantity has increased or decreased relative to its original value.

2. How the Calculator Works

The calculator uses the percentage change formula:

Key points:

• Positive result indicates an increase
• Negative result indicates a decrease
• The denominator (Old Value) cannot be zero
• Expressed as a percentage (%)

3. Practical Applications

Common uses: Financial analysis (stock prices, revenue growth), scientific measurements, population studies, performance metrics, and any situation tracking changes over time.

4. Using the Calculator

Instructions: Enter the original (old) value and the new value. The calculator will show the percentage change and indicate whether it's an increase or decrease.

Note: If the old value was zero, percentage change cannot be calculated (division by zero is undefined).

5. Frequently Asked Questions (FAQ)

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

Q2: How is this different from percentage difference?
A: Percentage change compares two values over time, while percentage difference compares two simultaneous values without time component.

Q3: Why can't I calculate percentage change when old value is zero?
A: Mathematically, division by zero is undefined. In practical terms, you can't calculate percentage change from nothing.

Q4: What's considered a significant percentage change?
A: This depends entirely on context. In finance, 5% might be significant for stocks, while in scientific measurements, 0.5% might be crucial.

Q5: Can percentage change be more than 100%?
A: Yes, when the new value is more than double the old value, the percentage change exceeds 100%.