-71.06% is the change from 311 to 90
Calculation steps:
[( 90 - 311 ) ÷ 311] x 100 = -71.06%
Formula
Percentage change = [(90 - 311) / 311] x 100
Subtract the new number by the original number
90 - 311 = -221
-221 ÷ 311 = -0.7106109324758842
-0.7106109324758842 x 100 = -71.06%