63.85% is the change from 509 to 834
Calculation steps:
[( 834 - 509 ) ÷ 509] x 100 = 63.85%
Formula
Percentage change = [(834 - 509) / 509] x 100
Subtract the new number by the original number
834 - 509 = 325
325 ÷ 509 = 0.6385068762278978
0.6385068762278978 x 100 = 63.85%