141.18% is the change from 340 to 820
Calculation steps:
[( 820 - 340 ) ÷ 340] x 100 = 141.18%
Formula
Percentage change = [(820 - 340) / 340] x 100
Subtract the new number by the original number
820 - 340 = 480
480 ÷ 340 = 1.411764705882353
1.411764705882353 x 100 = 141.18%