-96.76% is the change from 648 to 21
Calculation steps:
[( 21 - 648 ) ÷ 648] x 100 = -96.76%
Formula
Percentage change = [(21 - 648) / 648] x 100
Subtract the new number by the original number
21 - 648 = -627
-627 ÷ 648 = -0.9675925925925926
-0.9675925925925926 x 100 = -96.76%