840.7% is the change from 86 to 809
Calculation steps:
[( 809 - 86 ) ÷ 86] x 100 = 840.7%
Formula
Percentage change = [(809 - 86) / 86] x 100
Subtract the new number by the original number
809 - 86 = 723
723 ÷ 86 = 8.406976744186046
8.406976744186046 x 100 = 840.7%