I just wanted to get back to this epidemiology question. It's really what Mark also followed up on.
If the epidemiology suggests that the real risk is a certain group in society—it could be the very young, it could be the very elderly—and firefighters and all front-line health care workers are going to largely be exempt from those criteria, are you saying that firefighters and all front-line health care workers should always be tier 1? Or are you suggesting that there should be room for more tiering, or finer prioritization sequencing, under these guidelines?