The ratio of the adjusted or net retention volume (time) or retention factor of a component relative to that of a standard, obtained under identical conditions: $$r=\frac{V_{\text{R}i}^{{}^{\prime }}}{V_{\text{R}\left(\text{st}\right)}^{{}^{\prime }}}=\frac{V_{\text{N}i}}{V_{\text{N}\left(\text{st}\right)}}=\frac{t_{\text{R}i}^{{}^{\prime }}}{t_{\text{R}\left(\text{st}\right)}^{{}^{\prime }}}=\frac{k_i}{k_{\text{st}}}$$ Depending on the relative position of the peak corresponding to the standard compound in the chromatogram, the value of $r$ may be smaller, larger or identical to unity.