-86.37% is the change from 609 to 83
Calculation steps:
[( 83 - 609 ) ÷ 609] x 100 = -86.37%
Formula
Percentage change = [(83 - 609) / 609] x 100
Subtract the new number by the original number
83 - 609 = -526
-526 ÷ 609 = -0.8637110016420362
-0.8637110016420362 x 100 = -86.37%