Relation between the radius enclosing 68% of the total CO flux (scaled at the median distance of the region, and deprojected with inclination) and the flux enclosed by that radius for the entire Lupus CO disk population. Lines represent optically thick emission of CO with an average temperature of 30 (orange) and 20 K (black dash-dotted). Objects with outflows within the measured radius are considered to be upper limits in F_CO .