Fraction f of quiescent injected comets with respect to the total number (6119) plotted as a histogram versus the inverse of the semi-major axis at injection (the upper horizontal scale gives the corresponding semi-major axis). Two percent of the injected comets have a_inj < 10000 AU and fall to the right of the diagram. In the upper panel, the dark-blue area corresponds to comets belonging exclusively to set G, the sky-blue area corresponds to comets belonging to sets G and G′ but not to set S, the grey area corresponds to comets belonging to sets G and S, the red area corresponds to comets belonging to only set S, and the white area to comets belonging to neither set. In the lower panel, the green line gives the estimated fraction of injections when the stellar perturbations are turned off during the last revolution. The orange and grey areas correspond to the excess and shortage, respectively, of the number of injections in this case.