900% is the change from 82 to 820
Calculation steps:
[( 820 - 82 ) ÷ 82] x 100 = 900%
Formula
Percentage change = [(820 - 82) / 82] x 100
Subtract the new number by the original number
820 - 82 = 738
738 ÷ 82 = 9
9 x 100 = 900%
Example