-66.22% is the change from 820 to 277
Calculation steps:
[( 277 - 820 ) ÷ 820] x 100 = -66.22%
Formula
Percentage change = [(277 - 820) / 820] x 100
Subtract the new number by the original number
277 - 820 = -543
-543 ÷ 820 = -0.6621951219512195
-0.6621951219512195 x 100 = -66.22%