-80.31% is the change from 645 to 127
Calculation steps:
[( 127 - 645 ) ÷ 645] x 100 = -80.31%
Formula
Percentage change = [(127 - 645) / 645] x 100
Subtract the new number by the original number
127 - 645 = -518
-518 ÷ 645 = -0.8031007751937984
-0.8031007751937984 x 100 = -80.31%