-50% is the change from 622 to 311
Calculation steps:
[( 311 - 622 ) ÷ 622] x 100 = -50%
Formula
Percentage change = [(311 - 622) / 622] x 100
Subtract the new number by the original number
311 - 622 = -311
-311 ÷ 622 = -0.5
-0.5 x 100 = -50%
Example