-90.06% is the change from 312 to 31
Calculation steps:
[( 31 - 312 ) ÷ 312] x 100 = -90.06%
Formula
Percentage change = [(31 - 312) / 312] x 100
Subtract the new number by the original number
31 - 312 = -281
-281 ÷ 312 = -0.9006410256410257
-0.9006410256410257 x 100 = -90.06%