Ideally you'd see a new set of warnings every two years or so, or some period in that range. There's not a straight answer, because different consumers respond differently. There're always new young people coming along and new Canadians exposed to them for the first time. As well, when you or your wife or your daughter becomes pregnant, you're going to look at an existing warning in a different way. That life-changing event may suddenly prompt the warning to have a renewed impact for that particular individual.
We're seeing more countries that change warnings after a period of time--12 months, 18 months, two years, two and a half years, and so on.