-18.62% is the change from 811 to 660
Calculation steps:
[( 660 - 811 ) ÷ 811] x 100 = -18.62%
Formula
Percentage change = [(660 - 811) / 811] x 100
Subtract the new number by the original number
660 - 811 = -151
-151 ÷ 811 = -0.18618988902589395
-0.18618988902589395 x 100 = -18.62%