 As well as taxonomic groups, RLIs can show trends in extinction risk according to biogeographic realm, habitat type, and dominant threat process.Producing indices of change in extinction risk by comprehensively assessing whole species groups, while feasible for well studied groups with relatively few species, is not suitable for all taxonomic groups.Assessing every species in the larger and lesser known groups which comprise the majority of the world’s biodiversity, such as fungi, invertebrates (particularly insects) and plants, is not practical.