We present updated molecular abundances in 20 comets observed since 1985, using different ground-based high resolution infrared spectrometers.With this technique it is possible to sample emission lines produced by solar-pumped fluorescence of primary molecules released directly from the nucleus, and to investigate cosmogonic indicators such as rotational temperatures, production rates and mixing ratios, that are expected to remain unaltered since the comet's formation. Our results show that

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... of the previous published results contain inaccuracies introduced by the continuous evolution of the algorithms used for interpreting fluorescence in comets; moreover, for some species, we measure molecular abundances not reported in the past due to the lack of specific molecular models. Our revision impacts mostly comets that were observed before 2011, which constitute the majority of targets in our database. The correct statistics and interpretation of the updated molecular abundances, may yield important clues regarding the conditions present in the proto-planetary disk, when/where a specific comet formed, and can help us in building a chemical taxonomy for these bodies.