Illustration: Kerrie Leishman It's a question of what's likely to happen to their incomes and what's happening to their wealth. Our wealth is our assets (property, superannuation and other financial investments, and money in the bank) less our liabilities (mainly debts). Wealth is like congealed income. We can usually turn it back into money should we need to. Some of it produces income (rental properties, financial investments) and some reduces our need for income, such as when we live in our own homes rather than renting. We add to our wealth when we save some of our annual income. Most of us save more than we think we do, by paying off a mortgage over 20 or 30 years, or by having our employer fulfil the government's requirement to put 9.5 per cent of our wage into super. We also add to our wealth when the market value of the assets we own rises – "capital gain". And, of course, when we inherit the wealth of our relatives or receive a gift of money from them.

Illustration: John Spooner. The wealth of Australian households has grown a lot over the years, even after allowing for inflation, as all the figures I'll quote do. But the report, by John Daley and Danielle Wood, finds that over the past decade, older households captured most of the growth in the nation's wealth. Despite the global financial crisis, households aged between 65 and 74 in 2011-12 were, on average, $215,000 better off than households of that age range were eight years earlier. Those aged 55 to 64 were $173,000 richer, on average. But the average household in the 35 to 44 age group was only $80,000 richer. And get this: those aged 25 to 34 actually had less wealth than people of the same age 8 years earlier. Why? Various developments have conspired to bring this disparity about. Probably the biggest is what's happened to house prices and home ownership.

Rates of home ownership have fallen over the past two decades for all but the oldest households, the report finds. Going further back to 1981, more than 60 per cent of 25 to 34-year-olds were home owners. Thirty years later only 48 per cent of people in that age group were owners. An increasing proportion of those born after 1970 will never get on the property ladder, according to the authors. If increasing education debts aren't already discouraging younger households from taking out mortgages, it sounds like it won't be long before they will be. This means a higher proportion of the younger generation missed out on rising housing wealth as house prices boomed. Between 1995 and 2012, house prices increased by an average of 4.3 per cent a year faster than inflation. This was much faster than the rise in full-time wages. The boom was caused by the greater availability of home loans, the return to low inflation in the mid-1990s and by our failure to build enough new dwellings to keep up with population growth. The later you were to get in on it, the less the boom's capacity to increase your wealth, particularly because you had to borrow so much to join. But the worst of it for young people is that, though house prices are likely to stay high (making it hard to afford the entry fee), they can't possibly keep rising at the same rate (meaning the prize for getting in won't be as big as it used to be).

There's more to the problem than housing, however. Incomes also grew fastest for older people, allowing them to add more to their wealth through saving. In 2004, households aged 55 to 64 were net spenders; by 2010, with average annual incomes $4600 higher, their net annual saving was $2700. Although households aged 25 to 34 kept their spending controlled, their average incomes increased by $3100 and their saving by $1500. A big part of the reason for this is that, over the years, government spending and taxation policies have become more favourable to the elderly than they were. The age pension's been made more generous while income from super is now tax-free. Who has gained most from the big budget deficits we've been running since 2009? The old. Who will eventually have to pick up most of the tab? The young. All this wouldn't be such a worry if we could be confident that incomes will keep growing as strongly in the future as they have been for 70 years. They may.

But it isn't hard to think of reasons why they may not – including the thing none of us is allowed even to think about: climate change. Ross Gittins is economics editor.