67% is the change from 400 to 668
Calculation steps:
[( 668 - 400 ) ÷ 400] x 100 = 67%
Formula
Percentage change = [(668 - 400) / 400] x 100
Subtract the new number by the original number
668 - 400 = 268
268 ÷ 400 = 0.67
0.67 x 100 = 67%
Example