-18.47% is the change from 666 to 543
Calculation steps:
[( 543 - 666 ) ÷ 666] x 100 = -18.47%
Formula
Percentage change = [(543 - 666) / 666] x 100
Subtract the new number by the original number
543 - 666 = -123
-123 ÷ 666 = -0.18468468468468469
-0.18468468468468469 x 100 = -18.47%