The mass loss rate as a function of time for models M1a and M1b (top-left panel), M2a, M2b and M2c (top-right panel), M3a and M3b (bottom-left panel) and M4a and M4b (bottom-right panel). The caption on the top of each diagram indicates the model that a given curve type represents. The mass loss rate is in units of 10^-7   M_⊙ yr^-1 for models M2, M3 and M4 and in units of 10^-8   M_⊙ yr^-1 for models M1.