Proportion of pure δ Scuti stars with constant (Cte) or variable (Var) modes for all the sample and for different evolutionary stages. This last kind can be differentiated by the shape of the multiplet: one sidelobe (One), symmetric (Sym) or asymmetric (Asym) sidelobes. (Bin) indicates the proportion of binary stars detected with this method (see text). RMC indicates the proportion of this kind of star that show multiplets affected by resonant mode coupling (see text).