-90% is the change from 930 to 93
Calculation steps:
[( 93 - 930 ) ÷ 930] x 100 = -90%
Formula
Percentage change = [(93 - 930) / 930] x 100
Subtract the new number by the original number
93 - 930 = -837
-837 ÷ 930 = -0.9
-0.9 x 100 = -90%
Example