Mass as function of galactocentric radius for clouds from our 3D map (top) and CO from Miville-Deschênes et al. (2017) (bottom) for galactocentric rings of 1 kpc thickness. In this plot, we exclude CO clouds from Miville-Deschênes et al. (2017) belonging to regions not covered by our map (e.g. parts of the fourth quadrant). The shaded area shows regions where our results are likely underestimated due to the lack of input data. We did not limit the azimuth range for each radial bin; however, due to the limitations in the map, for regions beyond a galactocentric radius of 2 kpc, our radial average only covers half of a circle (negative X in previous figures).