Parameters for the colour distribution fit described in Eq. (1) for the full sample (shaded bands) and for the for subsamples split into dDLR, environmental colour, and stellar mass (global and local), and the dustless sample. The number of SNe in each subsample is indicated above the corresponding points. The full points in the bottom plot show the refitted full model (c_int, σ_c, and τ_dust) on the subsample, and the empty points show the fixed intrinsic colour distribution with the fitted dust distribution.