-96.79% is the change from 655 to 21
Calculation steps:
[( 21 - 655 ) ÷ 655] x 100 = -96.79%
Formula
Percentage change = [(21 - 655) / 655] x 100
Subtract the new number by the original number
21 - 655 = -634
-634 ÷ 655 = -0.9679389312977099
-0.9679389312977099 x 100 = -96.79%