Figure 4.1
The Red List Index (RLI) for all bird species for 1988–2004 (250 genuine status changes out of 2,469 species in categories Extinct in the Wild (EW) to Near Threatened (NT) in at least one assessment), with hypothetical indices showing trends if no species had changed category, and if 10% of species in the categories from NT to Critically Endangered (CR) had been uplisted to a higher category of threat or downlisted to a lower category of threat over the period. Error bars for 2004 RLI value are based on estimated number of genuine status changes for 2000–2004 not yet detected owing to information time-lags (see Appendix 2d for further details of methods).