How to Calculate Percentage Increase Subtract final value minus starting value Divide that amount by the absolute value of the starting value Multiply by 100 to get. Percentage increase and decrease formulas. Check your answer using the percentage decrease calculator.
For example to calculate the Monthly Change and Total Change.
The new quantity must be less than the original or the change will be an increase. Input this into the formula below. Percentage increase and decrease formulas. Lets assume you had 50 yesterday.