Evolution of the median sSFR as a function of redshift (left panel) and stellar mass (right panel). Open stars and open circles correspond to the values measured assuming a log-normal and a double-exponential profiles, respectively. The solid lines correspond to the fit using Eq. (5) and b independent of M⋆. Left: each color corresponds to a stellar mass bin (blue: 9.5−10 dex, green: 10−10.5, red: 10.5−11 and black 11−11.5). The dashed lines are obtained with b varying in each mass bin. Right: each color corresponds to a redshift bin from 0.2−0.4 (cyan) to 1.2−1.4 (black). The dotted lines are obtained using log (sSFR) ∝ log (M_⋆) (i.e., the standard definition in the literature). The solid line corresponds to log (sSFR) ∝ −0.17 M_⋆