-13.62% is the change from 668 to 577
Calculation steps:
[( 577 - 668 ) ÷ 668] x 100 = -13.62%
Formula
Percentage change = [(577 - 668) / 668] x 100
Subtract the new number by the original number
577 - 668 = -91
-91 ÷ 668 = -0.13622754491017963
-0.13622754491017963 x 100 = -13.62%