-17.29% is the change from 642 to 531
Calculation steps:
[( 531 - 642 ) ÷ 642] x 100 = -17.29%
Formula
Percentage change = [(531 - 642) / 642] x 100
Subtract the new number by the original number
531 - 642 = -111
-111 ÷ 642 = -0.17289719626168223
-0.17289719626168223 x 100 = -17.29%