-76.5% is the change from 668 to 157
Calculation steps:
[( 157 - 668 ) ÷ 668] x 100 = -76.5%
Formula
Percentage change = [(157 - 668) / 668] x 100
Subtract the new number by the original number
157 - 668 = -511
-511 ÷ 668 = -0.7649700598802395
-0.7649700598802395 x 100 = -76.5%