Calculate percent increase and decrease
Percentage change = ((New - Original) / Original) × 100%. Positive values = increase, negative = decrease. Used for business metrics, stock market, growth analysis, and statistics.
Subtract original from new, divide by original, multiply by 100. Example: (1250-1000)/1000 × 100 = 25% increase.
Percentage change undefined when original is zero. Use absolute change instead.