138.37% is the change from 344 to 820
Calculation steps:
[( 820 - 344 ) ÷ 344] x 100 = 138.37%
Formula
Percentage change = [(820 - 344) / 344] x 100
Subtract the new number by the original number
820 - 344 = 476
476 ÷ 344 = 1.3837209302325582
1.3837209302325582 x 100 = 138.37%