The percent change can be evaluated as,
First determine the change in the quantity, Change in quantity is equal to the difference between final amount and initial amount.
Then divide the change in quantity by initial amount of quantity.
Multiply the obtained result by 100 to obtain the results in percentage.
The final amount can be determined by adding the product of percent change and initial amount to the initial amount.
The value of percent change should be divided by 100 in order to convert percentage into the decimal.