Sales of homes under $400,000 are declining.

It would seem like Australian dwellings are increasingly becoming more expensive this year. According to the latest figures from CoreLogic, the share of affordable homes in the total number of sales has already started to decline.

CoreLogic defines affordable homes as those with price tags below $400,000. Over the course of the 2017-18 financial year, only 29.2% of all houses and 34.6% of units sold were considered affordable.

Combined capital city figures have slumped to a historic low — 13.9% house sales and 25.8% unit sales were under $400,000 over the past financial year, down from 16.2% and 27.1%, respectively.

"Although capital city dwelling values are falling, there continue to be fewer sales occurring below the $400,000 threshold," CoreLogic's Cameron Kusher said.

In Sydney, for instance, affordable houses and units accounted for a measly 2.5% and 5.8% of the total sales. On the other hand, 2.7% of Melbourne houses sold for less than $400,000, was down from 9.5% over the previous year. The share of affordable unit sales also went down to 21.5% from 28%.

While more affordable homes can be found in regional areas, the trend was still apparent. In fact, 49.6% of all regional house sales and 57.3% of all unit sales were for less than $400,000, down from 51.6% and 58%, respectively.