The overall rates of an isothermal catalytic reaction using spherical catalyst particles of diameters 1 mm and 2 mm are $r_A$$_1 and r_A$$_2$ (in mol (kg-catalyst)$^{-1}$ h$^{-1}$), respectively. The other physical properties of the catalyst particles are identical. If pore diffusion is very high, the ratio $r_A$$_2/r_A$$_1$ is $\_\_\_\_\_\_$