800% is the change from 91 to 819
Calculation steps:
[( 819 - 91 ) ÷ 91] x 100 = 800%
Formula
Percentage change = [(819 - 91) / 91] x 100
Subtract the new number by the original number
819 - 91 = 728
728 ÷ 91 = 8
8 x 100 = 800%
Example