-78.97% is the change from 642 to 135
Calculation steps:
[( 135 - 642 ) ÷ 642] x 100 = -78.97%
Formula
Percentage change = [(135 - 642) / 642] x 100
Subtract the new number by the original number
135 - 642 = -507
-507 ÷ 642 = -0.7897196261682243
-0.7897196261682243 x 100 = -78.97%