Mike Callaghan reminds us that where we are on the global GDP ranking may not be all that important to how well we live. When the press tries to dramatise the relationship between global rankings and our prospects of keeping a place at the G20 table, there is another point to be made: G20 membership is not just about size of GDP (however measured).

Look at PwC's list of 20 biggest-GDP countries in 2050 and ask yourself whether this would be the best group to sort out global economic issues:

When the original G20 grouping was formed in 1999 among finance ministers and central bank governors, there was a lot of elbowing and shoving from countries which were surprised to be excluded (Spain and Holland come to mind). The case for Australia’s inclusion was not just about GDP (where we were marginal, even then), but on the contribution Australia could make to the new group, consciously structured to represent a newer look for global governance. Was it better to have an Asian-focused new-world country with a successful economy (which had just shown itself to be a useful player in the Asian crisis), or yet one more European representative of the Old Order?

If we see value in staying in the G20, how do we ensure that we are such a valuable member that there will be a quorum to retain us? Let's tick off a couple of examples already clocked up. First off, we ran a good show when it was our turn as G20 chair. Second, our sterling performance as chair of the UN Security Council was widely noted.

If G20 membership depends on GDP, we know we've lost already. If we want to be there, we've got to work to ensure that it is about much more than GDP.