Came across something interesting that should be borne in mind when comparing GDP growth statistics: http://www.economist.com/node/10852462 . Essentially, when using GDP growth as a means of comparing the effectiveness of different nations' economic practices, it makes far more sense use to GDP growth per capita, as this accounts for different population growth rates. Comparing America and Japan, for instance, the former has had strong population growth over the past decade, whilst the latter's population has been stagnant or declining. GDP growth per capita accounts for this, and shows that in terms of economic growth per person Japan actually out-performed the US for quite a few years, in spite of common opinion to the contrary. Hence the argument that America's superior GDP growth over the past decade suggests America's economic practices trump Japan's is incorrect, as America's superior GDP growth was due largely to superior population growth, and hence reflects more on immigration policies and fertility rates, not necessarily on how conducive its economic and political structures are to growth.
The point is: take international comparisons of economic growth with a grain of salt, if they don't account for differences in population growth, else credit may be given to a nation's economic policies that should really only given to its fertility rate and immigration policies. Also a good example of how econometrics can be used to mislead, creating the general impression that Japan's economy was stagnant over the past decade when in reality the wealth of its citizens (GDP per capita) was slowly but steadily increasing.
He speaks to this very topic...in what is one of the best talks I've ever heard...