83.6% is the change from 311 to 571
Calculation steps:
[( 571 - 311 ) ÷ 311] x 100 = 83.6%
Formula
Percentage change = [(571 - 311) / 311] x 100
Subtract the new number by the original number
571 - 311 = 260
260 ÷ 311 = 0.8360128617363344
0.8360128617363344 x 100 = 83.6%