-15.61% is the change from 660 to 557
Calculation steps:
[( 557 - 660 ) ÷ 660] x 100 = -15.61%
Formula
Percentage change = [(557 - 660) / 660] x 100
Subtract the new number by the original number
557 - 660 = -103
-103 ÷ 660 = -0.15606060606060607
-0.15606060606060607 x 100 = -15.61%