Upper panel: The relation of the H₂ column density and the H I column density. Lower panel: Relation of the H₂ column density and the integrated intensity of CO (1–0). The red and black points denote sightlines using the ﹩{N}_{{\rm{H}}}/E(B-V)﹩ conversion factors of Nguyen et al. (2018) and Bohlin et al. (1978), respectively. The empty red circles denote sightlines with H I opacity correction. The red dotted lines show the fit results (points with an upper limit are not included).