That's really a very good question.
The first thing to say is that this system is only just being rolled out. One supermarket in particular has quite a lot of its products marked with traffic light labels, but other supermarkets and indeed manufacturers are just rolling the process out. So at the moment it's too early to have any really robust information about the consequences.
There is anecdotal information about people changing purchasing behaviour and some change in the sales of high-fat products, for example, which have dropped, whereas healthier products seem to have gone up. But the more important thing, I think, is that you will know—I'm sure you will have heard—that Tesco and the majority of the manufacturers have introduced a different system of front-of-pack labelling, which is not the same as the one the agency wants. Rather than the two sides, as it were, fighting each other, what we have agreed to do is to set up the research that will look, in 18 months' time, on a rolling process, at what form of labelling has changed consumers' behaviour the most, and that's been put out to an independent group headed by the government's chief social scientist.
The purpose of that is precisely as you suggest, to get the real evidence as to what works or what works less well. I think that's going to be quite exciting, because actually, in one sense we've just engaged 55 million U.K. consumers in a huge piece of research around consumer behaviour.
Do you want to add, Gill?