Peak molecular abundances in the CSEs of AGB stars of different chemical types: M-type stars R Dor and IK Tau, S-type stars χ Cyg and W Aql, and C-type stars V Aql and IRC +10 216. We note that the high SiS abundance for IK Tau is only representative of a geometrically small component centred on the star, after which depletion is very efficient and the abundance drops roughly four orders of magnitude. See text for further discussion and references. We have included error bars only for W Aql for the sake of visibility. The error bars correspond to the values specified in Table C.1 and we note that they are often smaller than the plotting symbol. Upper limits are indicated with downwards arrows. Molecules that were not previously identified towards W Aql are highlighted in boldface font on the horizontal axis.