During the next several years, the market for HCV drugs in the US and EU will be limited not so much by the number of patients with chronic HCV infection, but rather by the number of treating physicians and how many prescriptions they can write per year—i.e. the maximum throughput of the HCV medical establishment, which is approximately 350K patients per year.Dew: That strikes me as the most important assumption in your model. What does the evidence behind it consist of, if you don't mind my asking?