-85.67% is the change from 635 to 91
Calculation steps:
[( 91 - 635 ) ÷ 635] x 100 = -85.67%
Formula
Percentage change = [(91 - 635) / 635] x 100
Subtract the new number by the original number
91 - 635 = -544
-544 ÷ 635 = -0.8566929133858268
-0.8566929133858268 x 100 = -85.67%