-85.91% is the change from 660 to 93
Calculation steps:
[( 93 - 660 ) ÷ 660] x 100 = -85.91%
Formula
Percentage change = [(93 - 660) / 660] x 100
Subtract the new number by the original number
93 - 660 = -567
-567 ÷ 660 = -0.8590909090909091
-0.8590909090909091 x 100 = -85.91%