-85.32% is the change from 620 to 91
Calculation steps:
[( 91 - 620 ) ÷ 620] x 100 = -85.32%
Formula
Percentage change = [(91 - 620) / 620] x 100
Subtract the new number by the original number
91 - 620 = -529
-529 ÷ 620 = -0.853225806451613
-0.853225806451613 x 100 = -85.32%