-67.56% is the change from 820 to 266
Calculation steps:
[( 266 - 820 ) ÷ 820] x 100 = -67.56%
Formula
Percentage change = [(266 - 820) / 820] x 100
Subtract the new number by the original number
266 - 820 = -554
-554 ÷ 820 = -0.675609756097561
-0.675609756097561 x 100 = -67.56%