-49.2% is the change from 311 to 158
Calculation steps:
[( 158 - 311 ) ÷ 311] x 100 = -49.2%
Formula
Percentage change = [(158 - 311) / 311] x 100
Subtract the new number by the original number
158 - 311 = -153
-153 ÷ 311 = -0.4919614147909968
-0.4919614147909968 x 100 = -49.2%