-23.3% is the change from 837 to 642
Calculation steps:
[( 642 - 837 ) ÷ 837] x 100 = -23.3%
Formula
Percentage change = [(642 - 837) / 837] x 100
Subtract the new number by the original number
642 - 837 = -195
-195 ÷ 837 = -0.23297491039426524
-0.23297491039426524 x 100 = -23.3%