Mass accretion rates versus stellar age for our HAeBes (solid symbols, upper and lower limits are represented with triangles) and T Tauri stars from Hartmann et al. (1998) (crosses). The best fits for our sample are represented with solid and dashed lines, for the exponential (τ = 1.3 Myr) and power-law (η = 1.8) expressions, respectively. 51 Oph was not considered for the fit. The dotted line is the best power-law fit for T Tauri stars (η  ~  1.5; see Hartmann et al. 1998; Calvet et al. 2000; Muzerolle et al. 2000).