-4.35% is the change from 690 to 660
Calculation steps:
[( 660 - 690 ) ÷ 690] x 100 = -4.35%
Formula
Percentage change = [(660 - 690) / 690] x 100
Subtract the new number by the original number
660 - 690 = -30
-30 ÷ 690 = -0.043478260869565216
-0.043478260869565216 x 100 = -4.35%