The S&P/ASX 200 Index (ASX: XJO) has had a rough day in trading so far. At the time of writing, the ASX 200 is down by 0.12% to 7,416 points. However, the Commonwealth Bank of Australia (ASX: CBA) share price is performing even worse.
CBA shares are currently down 0.68% to $100.61 a share. While that figure is clearly trailing the ASX 200 today, it's also trailing that of CBA's big four banking peers.
While all the four major ASX banking shares are currently in the red, CBA is coming in dead last.
The best performer so far today is the Australia and New Zealand Banking Group Ltd (ASX: ANZ) share price, which is down by 0.22% at $27.56 a share.
Westpac Banking Corp (ASX: WBC) shares are currently trading for $25.56 each, down 0.29%, while National Australia Bank Ltd (ASX: NAB) shares are down by 0.46% to $28.05 a share.
That leaves CBA as the worst-performing ASX major bank today so far.
What's up with the CBA share price?
Well, it's not entirely clear.
There are a few possible explanations though. For one, there have been some recent concerns that the CBA share price might have gotten a little ahead of itself in regards to valuation. Just last week, we covered how an expert investor thinks CBA "no longer deserves its premium" and "the glory days for the CBA share price might soon be over".
Another recent concern has been the exploding housing market. While many homeowners have no problem watching their castle rise in value, affordability concerns have been rising.
According to a report from news.com.au today, new economic modelling suggests that 2 in 5 households in New South Wales are currently under "mortgage stress". This means they are spending more on their cost of living than what they are earning.
The report also states "homeowners in much of Sydney cannot afford their mortgages and would be in financial trouble if there was a rapid rise in interest rates".
CBA is one of, if not the, largest mortgage writers in the country. As such, it makes sense that investors might get nervous over these kinds of figures.
At the current CBA share price, this ASX bank has a market capitalisation of $179.7 billion, a price-to-earnings (P/E) ratio of 21.5 and a dividend yield of 3.46%.
