-50.88% is the change from 623 to 306
Calculation steps:
[( 306 - 623 ) ÷ 623] x 100 = -50.88%
Formula
Percentage change = [(306 - 623) / 623] x 100
Subtract the new number by the original number
306 - 623 = -317
-317 ÷ 623 = -0.5088282504012841
-0.5088282504012841 x 100 = -50.88%