-85.48% is the change from 620 to 90
Calculation steps:
[( 90 - 620 ) ÷ 620] x 100 = -85.48%
Formula
Percentage change = [(90 - 620) / 620] x 100
Subtract the new number by the original number
90 - 620 = -530
-530 ÷ 620 = -0.8548387096774194
-0.8548387096774194 x 100 = -85.48%