-90.61% is the change from 990 to 93
Calculation steps:
[( 93 - 990 ) ÷ 990] x 100 = -90.61%
Formula
Percentage change = [(93 - 990) / 990] x 100
Subtract the new number by the original number
93 - 990 = -897
-897 ÷ 990 = -0.906060606060606
-0.906060606060606 x 100 = -90.61%