-83.57% is the change from 645 to 106
Calculation steps:
[( 106 - 645 ) ÷ 645] x 100 = -83.57%
Formula
Percentage change = [(106 - 645) / 645] x 100
Subtract the new number by the original number
106 - 645 = -539
-539 ÷ 645 = -0.8356589147286821
-0.8356589147286821 x 100 = -83.57%