Identify the base value (the whole) and the part value (the amount you’re comparing)
Percentage of a number:
Percent = (part ÷ whole) × 100%
Find the part from a percentage:
part = (percent ÷ 100) × whole
Find the whole from a percentage:
whole = part ÷ (percent ÷ 100)
Convert a decimal to a percentage:
percent = decimal × 100%
Convert a percentage to a decimal:
decimal = percent ÷ 100
Percentage increase:
increase % = ((new − old) ÷ old) × 100%
Percentage decrease:
decrease % = ((old − new) ÷ old) × 100%
Percentage change (general):
change % = ((new − old) ÷ old) × 100%