Housing affordability has improved more in Ireland than in any developed country in the English-speaking world, an international report has found.

The ninth annual Demographia International Housing Affordability survey found house prices in Ireland are now on average 3.2 times gross annual incomes, making Ireland and the US (3.1) the most affordable of seven countries surveyed.

The survey has been tracking house prices in Australia, Canada, China (Hong Kong), Ireland, New Zealand, the UK and the US over the last nine years.

The survey is confined to English-speaking countries that have similar patterns of home ownership and excludes European countries where home ownership is historically lower.

It defines affordability as a situation where house prices are three times gross annual income before tax, or less.

The only cities with a population of more than one million to meet the criteria were all in the US. There were 20 such cities, most of which have been badly affected by deindustrialisation, including Detroit, Cincinnati, Cleveland and Indianapolis.

After Edmonton in Canada, Dublin was the most affordable of the major metropolises. House prices peaked at six times the average salary in Dublin in 2006; they have now dropped to 3.6 times the average salary.

Up until the late 1980s and early 1990s, house prices were a multiple of between two and three times’ average salaries in all the markets surveyed, before deteriorating in the years after that.

The survey says the principal reason for house inflation has been the curtailment in the supply of development land.

It also maintains there is a consistent pattern in all countries where there has been a tendency by vested interests to “cheer on” house-price inflation, as if houses were a “commodity like gold” instead of a basic necessity.

The cheapest city in Ireland relative to income is Waterford (2.5), followed by Limerick (3.1), Galway (3.2) and Cork (3.4).

In the last quarter of 2007, at the height of the property boom, house prices in Ireland were a multiple of 4.7 times the average gross salary.

By contrast Australia, the most popular destination of the current crop of Irish emigrants, has some of the most unaffordable urban housing. It uses just 0.04 per cent of its land area for housing.

The average house in Sydney costs 8.3 times the average salary, in Melbourne it’s 7.5 times salary, in Adelaide it’s 6.5 and in Perth it’s 5.6. The average home in a major Australian city costs 6.5 times the average salary.

New Zealand’s only major metropolis, Auckland, is also classified as being severely unaffordable, with house prices 6.7 times the average salary.

London is the fifth-most-unaffordable city surveyed, with house prices a multiple of 7.5 times gross salaries.

The UK has no major market where house prices are less than four times the average gross salary.