It's no different from the census long-form debate this country had. As I said, we know the profile of those who consent is different from the ones who don't consent. Our ability to essentially account for those who don't consent doesn't allow itself to be substituted or weighted up, if you like, to those who do, because those who consent don't look like the ones who don't.
We know the youth don't participate. We know in many cases single parents are too busy and they can't participate. So we miss data in many cases for the very audiences that policy-makers are trying to get a better handle on.