-33.96% is the change from 642 to 424
Calculation steps:
[( 424 - 642 ) ÷ 642] x 100 = -33.96%
Formula
Percentage change = [(424 - 642) / 642] x 100
Subtract the new number by the original number
424 - 642 = -218
-218 ÷ 642 = -0.3395638629283489
-0.3395638629283489 x 100 = -33.96%