-81.38% is the change from 666 to 124
Calculation steps:
[( 124 - 666 ) ÷ 666] x 100 = -81.38%
Formula
Percentage change = [(124 - 666) / 666] x 100
Subtract the new number by the original number
124 - 666 = -542
-542 ÷ 666 = -0.8138138138138138
-0.8138138138138138 x 100 = -81.38%