As ever housing affordability remains a hot topic. The latest little spot fire this week came via demographer, Bernard Salt’s venture into a hipster cafe where he saw young people buying a smashed avocado dish for $22 (I know, the shock). He mused “how can young people afford to eat like this? Shouldn’t they be economising by eating at home? How often are they eating out? Twenty-two dollars several times a week could go towards a deposit on a house”.

Now look, I could get outraged over this boomer-millennial war, but as a proud member of Gen X, I’d rather both sides shut up and let me listen to Nirvana on Spotify in peace.

But if one must take a side, as ever I’ll side with the evidence over the anecdote.

Suggesting that seeing a person in their 20s eating a $22 meal is somehow representative of any group is a pretty specious bit of research.

Baby boomers have already taken all the houses, now they're coming for our brunch | Brigid Delaney Read more

Perhaps that person buying the dish already owns a house or apartment, perhaps the avocado lover in question had decided he might as well buy a $22 bit of food given the likelihood of never being able to afford a house, given people over 50 are pushing up the prices as they frantically try to buy an investment property in order to negatively gear it.

But when you gotta file some dumb copy to make the yell-at-the-cloud clique smile, I guess you leave the research for the younger, more energetic folk.

Thankfully evidence abounds. And as is often the case, a graph showed it quite nicely.

Matt Cowgill, an economist and stout defender of the millennial, yesterday tweeted an excellent graph showing that according to the ABS’s household expenditure survey, people in households aged 25-34 actually spend more of their income now on housing than they did in 1989.

Not only that, they spend less of their income on food now than they did then.

Cowgill showed the data comparison of 1989 and 2010 which is the latest data we have (but the ABS has had regular such surveys going back to 1984).

A look at the amount of 25-24 year-olds income spent on housing, food, alcohol and recreation shows that, rather unsurprisingly, the big increase in housing expenditure came in the 2000s with the housing boom:

And far from being food gluttons, drunkards or spending all their money on slovenly “recreation”, in all three of those categories 25-34 year-olds spent less of their income than did their counterparts of earlier years.

This really should be no surprise to older folk – that is those now in Generation X (sigh) and above – because the same spending patterns have happened for them.

In 1984 households with the head aged 45-54 spent 7% of their income on housing costs. By 1999 this had risen marginally to 7.9%, but by 2010 it had boomed to 10.5%:

Rather unsurprisingly, when housing costs go up for one group, they also go up for others.

And anyone arguing that people spend less now on housing expenses than they did in the past has probably eaten a few too many dodgy avocados and best go have a lie down and take a nap.

One problem specific to youth now compared to the past is that not only are they in the process of trying to save up for a deposit, they are doing so at a time where rent is more expensive now than it once was.

Compare the annual price growth of rents and overall CPI over the past 15 years and again you see that for renters, costs have risen markedly compared to other items.

That’s great if you own an investment property and have been negative gearing it like mad; not so good if you are one renting while saving up to buy your first home:

What has also changed is the type of property a young person might be able to now buy.

In the past, Australia was very much a place where houses were built. But the latest housing boom, since the RBA cut rates in November 2011, has very much been a boom of construction of apartment and flats:

And the apartment boom has been most marked in Sydney:

Melbourne:

And Brisbane:

So big has this apartment boom been that the RBA has been worried that a glut of apartments in these cities might occur – where the supply of apartments outstrips demand and thus the price of the apartments crashes – or at least falls significantly.

In its latest Financial Stability Review released last Friday, the RBA even made special mention of the “Banks’ Exposures to Inner-city Apartment Markets” warning that “the large number of new apartments recently completed and currently under construction in many capital cities raises the risk of a marked oversupply in some geographic areas”.

And certainly the supply continues to come – with the total value of work on non-housing residential building still to be done now reaching a record $33.6bn:

The increase in supply is good for housing affordability – even if the affordability is likely to be first improved for those buying an apartment rather than a house. But such things filter through the system, and anything that allows younger people to get into the housing market in the first place is generally a good thing.

But should a glut occur and a housing market bubble bursts due to the surge of apartments, the flow-on might mean lower house prices, but the overall impact would see the economy as a whole as smashed as a $22 avocado brunch.

And you wouldn’t be able to blame the millennials for that.