-61.21% is the change from 642 to 249
Calculation steps:
[( 249 - 642 ) ÷ 642] x 100 = -61.21%
Formula
Percentage change = [(249 - 642) / 642] x 100
Subtract the new number by the original number
249 - 642 = -393
-393 ÷ 642 = -0.6121495327102804
-0.6121495327102804 x 100 = -61.21%