21.71% is the change from 668 to 813
Calculation steps:
[( 813 - 668 ) ÷ 668] x 100 = 21.71%
Formula
Percentage change = [(813 - 668) / 668] x 100
Subtract the new number by the original number
813 - 668 = 145
145 ÷ 668 = 0.21706586826347304
0.21706586826347304 x 100 = 21.71%