-70.83% is the change from 312 to 91
Calculation steps:
[( 91 - 312 ) ÷ 312] x 100 = -70.83%
Formula
Percentage change = [(91 - 312) / 312] x 100
Subtract the new number by the original number
91 - 312 = -221
-221 ÷ 312 = -0.7083333333333334
-0.7083333333333334 x 100 = -70.83%