-20.81% is the change from 841 to 666
Calculation steps:
[( 666 - 841 ) ÷ 841] x 100 = -20.81%
Formula
Percentage change = [(666 - 841) / 841] x 100
Subtract the new number by the original number
666 - 841 = -175
-175 ÷ 841 = -0.2080856123662307
-0.2080856123662307 x 100 = -20.81%