Histograms of the (a) redshift z, (b) extinction A(V) in the V band derived from the hydrogen Balmer decrement, (c) absolute g-band magnitude M_g corrected for the Milky Way extinction, (d) ‘observed’ absolute FUV magnitude M_FUV, i.e. the absolute magnitude derived from the extrapolation of the extinction-corrected SDSS spectrum and attenuated adopting extinction A(V) obtained from the Balmer hydrogen decrement, (e) stellar mass derived from the SED fitting of the extinction-corrected SDSS spectrum, (f) oxygen abundance 12 + logO/H, (g) [O III] λ5007/[O II] λ3727 ratio denoted as O₃₂, (h) [Ne III] λ3868/[O II] λ3727 ratio denoted as Ne3O2, (i) star-formation rate SFR derived from the extinction-corrected Hβ luminosity, (j) specific star-formation rate sSFR = SFR/(M_⋆/M_⊙), (k) – (n) equivalent widths of the [O II] λ3727, [O III] λ5007, Hβ + [O III] λ4959 + [O III] λ5007 and Hα emission lines, respectively, (o) – (q) extinction-corrected luminosities of the [O II] λ3727, [O III] λ5007 and Hαλ6563 emission lines, respectively, (r) ionising photon production efficiency derived from the extinction-corrected Hβ luminosity and extinction-corrected monochromatic luminosity at the rest-frame wavelength of 1500 Å, (s) extinction-corrected UV slope derived from the modelled rest-frame SED, (t) UV slope derived from the obscured SEDs with the extinction coefficient derived from the observed Balmer decrement adopting the Cardelli et al. (1989) reddening law with R(V) = 3.1. In all panels, histograms represented by the red and blue lines are for the total SDSS sample of CSFGs and for CSFGs with EW(Hβ) ≥ 100 Å, respectively.