-96.96% is the change from 657 to 20
Calculation steps:
[( 20 - 657 ) ÷ 657] x 100 = -96.96%
Formula
Percentage change = [(20 - 657) / 657] x 100
Subtract the new number by the original number
20 - 657 = -637
-637 ÷ 657 = -0.969558599695586
-0.969558599695586 x 100 = -96.96%