Mean mass accretion rate versus age. Open symbols represent the targets with mean EW_Hα ≤ 10 Å, while binaries are evidenced as upper limits. The big square represents the mean position of Cha II, taking into account the single stars with mean EW_Hα > 10 Å (vertical and horizontal error bars correspond to the standard deviations from the mean Ṁ_acc and age, respectively). The dashed lines mark minimum and maximum limits of Eq. (3), while dotted lines represent the analogous limits of the relationship derived for Cha I by Hartmann et al. (1998). The collection of viscous disk evolutionary models for solar-type stars with initial disk masses of 0.1−0.2 M_⊙, constant viscosity α = 10^-2, and viscosity exponent γ = 1 reported by Sicilia-Aguilar et al. (2010) is also displayed (filled region).