-84.93% is the change from 657 to 99
Calculation steps:
[( 99 - 657 ) ÷ 657] x 100 = -84.93%
Formula
Percentage change = [(99 - 657) / 657] x 100
Subtract the new number by the original number
99 - 657 = -558
-558 ÷ 657 = -0.8493150684931506
-0.8493150684931506 x 100 = -84.93%