-95% is the change from 620 to 31
Calculation steps:
[( 31 - 620 ) ÷ 620] x 100 = -95%
Formula
Percentage change = [(31 - 620) / 620] x 100
Subtract the new number by the original number
31 - 620 = -589
-589 ÷ 620 = -0.95
-0.95 x 100 = -95%
Example