-98.33% is the change from 660 to 11
Calculation steps:
[( 11 - 660 ) ÷ 660] x 100 = -98.33%
Formula
Percentage change = [(11 - 660) / 660] x 100
Subtract the new number by the original number
11 - 660 = -649
-649 ÷ 660 = -0.9833333333333333
-0.9833333333333333 x 100 = -98.33%