-66.14% is the change from 821 to 278
Calculation steps:
[( 278 - 821 ) ÷ 821] x 100 = -66.14%
Formula
Percentage change = [(278 - 821) / 821] x 100
Subtract the new number by the original number
278 - 821 = -543
-543 ÷ 821 = -0.6613885505481121
-0.6613885505481121 x 100 = -66.14%