Consider steady-state diffusion in a binary $\text{A-B}$ liquid at constant temperature and pressure. The mole-fraction of $A$ at two different locations is $0.8$ and $0.1$. Let $N_{A1}$ be the diffusive flux of $A$ calculated assuming $B$ to be non-diffusing, and $N_{A2}$ be the diffusive flux of $A$ calculated assuming equimolar counter-diffusion. The quantity $\dfrac{\left ( N_{A1} - N_{A2} \right )}{N_{A1}} \times 100$ is _________________ (rounded off to one decimal place).