The SF rate normalized to the solar values as a function of the galactocentric distance for the one-infall model with no inside-out formation. The data are taken by Rana et al. (1991) and are reported with the magenta points and relative error bars. With the red solid line we report, the reference static model S1N, whereas the dashed blue line is the model with a radial inflow of  − 1 km s^-1 (R1N1).