-15.58% is the change from 642 to 542
Calculation steps:
[( 542 - 642 ) ÷ 642] x 100 = -15.58%
Formula
Percentage change = [(542 - 642) / 642] x 100
Subtract the new number by the original number
542 - 642 = -100
-100 ÷ 642 = -0.1557632398753894
-0.1557632398753894 x 100 = -15.58%