Mass-loss rates Ṁ vs. mean dereddened colour indices for the sample of C-type Miras, adopted from Table 6 of Whitelock et al. (2006). Also shown are the corresponding results for the dynamical models. For the sake of completeness we mark the location in (J – K)₀ of model T with an arrow although this model does not develop a wind (i.e. Ṁ = 0). In addition, the empirical relation found by Le Bertre (1997) for galactic mass-losing AGB stars of spectral type C is drawn (dotted line). Overplotted is also the more recent fit derived by Gullieuszik et al. (2012) for C-rich giants in the LMC (dashed line).