-83.35% is the change from 931 to 155
Calculation steps:
[( 155 - 931 ) ÷ 931] x 100 = -83.35%
Formula
Percentage change = [(155 - 931) / 931] x 100
Subtract the new number by the original number
155 - 931 = -776
-776 ÷ 931 = -0.8335123523093448
-0.8335123523093448 x 100 = -83.35%