This took total seizures to 1,513 which included 403 different types of drugs, confiscated in 99 countries. Nineteen of the top 25 selling pharmaceuticals were among those seized, which had a total value of $3bn according to the PSI. Although it is not expressly stated it seems likely the $3bn is their worth if they were legitimate medicines. A breakdown of the regions, but not countries, of arrests has been made available by the PSI, with Asia accounting for around 40 per cent. Trailing Asia is Latin America and North America (US and Canada), with around 20 per cent of total arrests made in each region. This is in keeping with the 2006 PSI figures, which put China, the US, Brazil and India among the top five counterfeiters. The other nation in the top five for 2006 was Russia, which is clumped into a Eurasia block in 2007, including Eastern European, Turkey and the former Soviet Union. This group accounts for 10 per cent of seizures. Over 60 per cent of drugs seized were for treatment of erectile dysfunction and although a breakdown into individual medicines is not available it seems likely Viagra (sildenafil citrate) accounts for a sizeable chunk of this. Pfizer believes it loses $2bn a year in revenue from counterfeit Viagra, which had legitimate sales of $1.8bn in 2007. However, this revenue loss is based upon the assumption that everyone who purchased counterfeit Viagra would have had it prescribed by a physician if fakes were not available. This seems unlikely owing to Viagra and other erectile dysfunction drugs rise in popularity as a recreational drug, used by those not suffering from the ailment. Viagra's popularity among night club goers was being reported as far back as 1999 by the BBC. Although erectile dysfunction drugs are the most counterfeited the problem is not confined to this sector. Central nervous system therapeutics, such as anti-depressants, accounted for 20 per cent of the confiscations, with antipsychotic Zyprexa (olanzapine) said to be the most counterfeited of Eli Lilly's products. Lilly's own security officials claim counterfeits of all seven of its blockbusters were seized in raids in 2007, with fakes of Pfizer's nine top selling drugs said to be confiscated as well.