-33.87% is the change from 998 to 660
Calculation steps:
[( 660 - 998 ) ÷ 998] x 100 = -33.87%
Formula
Percentage change = [(660 - 998) / 998] x 100
Subtract the new number by the original number
660 - 998 = -338
-338 ÷ 998 = -0.33867735470941884
-0.33867735470941884 x 100 = -33.87%