-86.79% is the change from 666 to 88
Calculation steps:
[( 88 - 666 ) ÷ 666] x 100 = -86.79%
Formula
Percentage change = [(88 - 666) / 666] x 100
Subtract the new number by the original number
88 - 666 = -578
-578 ÷ 666 = -0.8678678678678678
-0.8678678678678678 x 100 = -86.79%