-96.71% is the change from 820 to 27
Calculation steps:
[( 27 - 820 ) ÷ 820] x 100 = -96.71%
Formula
Percentage change = [(27 - 820) / 820] x 100
Subtract the new number by the original number
27 - 820 = -793
-793 ÷ 820 = -0.9670731707317073
-0.9670731707317073 x 100 = -96.71%