In his Intergenerational Report of 2002 [pdf] and again in last week's discussion paper, he estimated that, by 2041-42, the annual cost of the age pension bill will have grown by 1.7 per cent of GDP, which is equivalent to less than $14 billion in today's dollars. That increase - which will take 40 years to build up - is about half the average increase for OECD countries and just a bit over a quarter of the increase New Zealand and Canada are facing.
And don't forget that government spending on the dole and family payments and education will be falling as a percentage of GDP as spending on age pensions and aged care is rising.
So it's little wonder Costello in his printed persona refers to the expected growth in spending on age pensions as 'manageable'.
(If you have it in your mind that Costello's been on about a rise in government spending equivalent to as much as 5 per cent of GDP - about $40 billion a year - that's because he sexed up his figures by adding a factor that has nothing to do with ageing: the likelihood that, as we continue getting richer over the next 40 years, we'll devote a higher proportion of our income to taking advantage of advances in medical technology.)
But if the budgetary costs of the ageing population aren't all that frightening, what on earth is all the fuss about? I thought you'd never ask.
The fuss is about an alternative prime minister who is frantically casting about for some ideas to distinguish him from the Man of Steel. His delivery on this issue has, if anything, been feebler than his actual policy.
'Demography is Destiny!' What does that actually mean? Apart from telling us the Costello speechwriters have decided: 'Alliteration is Argument!'?