-86.59% is the change from 619 to 83
Calculation steps:
[( 83 - 619 ) ÷ 619] x 100 = -86.59%
Formula
Percentage change = [(83 - 619) / 619] x 100
Subtract the new number by the original number
83 - 619 = -536
-536 ÷ 619 = -0.8659127625201939
-0.8659127625201939 x 100 = -86.59%