99.4% is the change from 335 to 668
Calculation steps:
[( 668 - 335 ) ÷ 335] x 100 = 99.4%
Formula
Percentage change = [(668 - 335) / 335] x 100
Subtract the new number by the original number
668 - 335 = 333
333 ÷ 335 = 0.9940298507462687
0.9940298507462687 x 100 = 99.4%