-34.11% is the change from 642 to 423
Calculation steps:
[( 423 - 642 ) ÷ 642] x 100 = -34.11%
Formula
Percentage change = [(423 - 642) / 642] x 100
Subtract the new number by the original number
423 - 642 = -219
-219 ÷ 642 = -0.3411214953271028
-0.3411214953271028 x 100 = -34.11%