-86.94% is the change from 666 to 87
Calculation steps:
[( 87 - 666 ) ÷ 666] x 100 = -86.94%
Formula
Percentage change = [(87 - 666) / 666] x 100
Subtract the new number by the original number
87 - 666 = -579
-579 ÷ 666 = -0.8693693693693694
-0.8693693693693694 x 100 = -86.94%