-15.02% is the change from 666 to 566
Calculation steps:
[( 566 - 666 ) ÷ 666] x 100 = -15.02%
Formula
Percentage change = [(566 - 666) / 666] x 100
Subtract the new number by the original number
566 - 666 = -100
-100 ÷ 666 = -0.15015015015015015
-0.15015015015015015 x 100 = -15.02%