-47.35% is the change from 642 to 338
Calculation steps:
[( 338 - 642 ) ÷ 642] x 100 = -47.35%
Formula
Percentage change = [(338 - 642) / 642] x 100
Subtract the new number by the original number
338 - 642 = -304
-304 ÷ 642 = -0.4735202492211838
-0.4735202492211838 x 100 = -47.35%