-16.82% is the change from 642 to 534
Calculation steps:
[( 534 - 642 ) ÷ 642] x 100 = -16.82%
Formula
Percentage change = [(534 - 642) / 642] x 100
Subtract the new number by the original number
534 - 642 = -108
-108 ÷ 642 = -0.16822429906542055
-0.16822429906542055 x 100 = -16.82%