1171.21% is the change from 66 to 839
Calculation steps:
[( 839 - 66 ) ÷ 66] x 100 = 1171.21%
Formula
Percentage change = [(839 - 66) / 66] x 100
Subtract the new number by the original number
839 - 66 = 773
773 ÷ 66 = 11.712121212121213
11.712121212121213 x 100 = 1171.21%