Well, it is arbitrary in that it's not fine tuned to say that you could put it immediately between 49 and 51. Whenever you have a border, there is a degree of arbitrariness about it. But the advice that we had was that, in broad terms, a care home with 50 or more people in it was more vulnerable to the introduction of coronavirus, even when there is none circulating in the care home today. That was the number that was advised to us as the best place to draw the line. In its specifics, it has a component of arbitrariness about it, as any number does, but it is not plucked out of the air, it is derived from the science that lies behind it, the nature of the care home sector, and the advice that then goes to Ministers.