100% is the change from 342 to 684
Calculation steps:
[( 684 - 342 ) ÷ 342] x 100 = 100%
Formula
Percentage change = [(684 - 342) / 342] x 100
Subtract the new number by the original number
684 - 342 = 342
342 ÷ 342 = 1
1 x 100 = 100%
Example