-15.15% is the change from 660 to 560
Calculation steps:
[( 560 - 660 ) ÷ 660] x 100 = -15.15%
Formula
Percentage change = [(560 - 660) / 660] x 100
Subtract the new number by the original number
560 - 660 = -100
-100 ÷ 660 = -0.15151515151515152
-0.15151515151515152 x 100 = -15.15%
Example