Upper half of each panel shows the accretion rates as a function of time found in our simulations (solid), expected from our theoretical model (dashed) and expected from Bondi-Hoyle accretion (dotted), respectively. The colour coding is as in Fig. 3. These rates are the derived from the quantity in the lower half of the panel, which is the cumulative amount of ISM accreted by the disc and star (solid lines). Our theoretical estimate based on the size of the disc (see Eq. (19)) is given by the dashed lines. The amount of accreted ISM expected from Bondi-Hoyle accretion is shown in dotted lines.