Multiplicity fraction of K and M dwarf stars in the Catalog of Systems. Left panel: Gaia CMD of primary, low-mass stars in the Catalog of Systems (with the overluminous stars shifted by Δ M_G = 2.5log₁₀∣2∣). Overlaid on the CMD are the contours of equal mass derived from the relation in Section 6 A. W. Mann et al. (2019). Right panel: multiplicity fraction for each mass bin across equal-volume distances. Each fraction is colored by its mass bin.