83.14% is the change from 421 to 771
Calculation steps:
[( 771 - 421 ) ÷ 421] x 100 = 83.14%
Formula
Percentage change = [(771 - 421) / 421] x 100
Subtract the new number by the original number
771 - 421 = 350
350 ÷ 421 = 0.831353919239905
0.831353919239905 x 100 = 83.14%