990.91% is the change from 77 to 840
Calculation steps:
[( 840 - 77 ) ÷ 77] x 100 = 990.91%
Formula
Percentage change = [(840 - 77) / 77] x 100
Subtract the new number by the original number
840 - 77 = 763
763 ÷ 77 = 9.909090909090908
9.909090909090908 x 100 = 990.91%