Another way in which the national insurance fund has been described, of course, is as 'the world's largest Ponzi scheme', as it has developed. I hope we will never recreate something in that image here in Wales. What we have the opportunity to do here, I think, is something similar to what Norway has done, for example, in relation to the windfall that it obtained when North Sea oil came on stream and they created a sovereign wealth fund, which is now producing vast dividends for the Norwegian people, on the basis of which their very high standard of living and social insurance and health provision and so on is substantially funded. We don't have wealth of oil but we do have the wealth in the creative abilities of our people. If we could isolate a small portion of national income for a sovereign wealth fund of this kind then we could perhaps help to square the circle of funding of the growing needs of an ageing population and of a health system that is going to be able to cure so many more conditions that, in the past, have led to early deaths. So, either way, part of the growing prosperity of a nation is in the health and well-being of its people and this fits in neatly with the Well-being of Future Generations (Wales) Act 2015 and consideration of taxes with that Act, I think, is absolutely vital if we're to make a success of devolution in this particular sphere.