Home affordability in Honolulu has long been at or near the bottom of the heap in comparison with Mainland cities, but a new study shows it's also more difficult to buy a home in Honolulu than in many international cities.

An analysis led by a St. Louis-based public policy organization ranked Honolulu the fourth least-affordable place to buy a single-family home out of 227 urban housing markets in Australia, Canada, Ireland, New Zealand, the United Kingdom and the U.S.

Three cities in California — Los Angeles, Salinas and San Francisco — were less affordable than Honolulu, or the county covering O'ahu. Just behind Honolulu was San Diego at fifth least affordable, followed by the first international city, Mandurah, Australia.

The Demographia International Housing Affordability Survey produces its rankings by dividing a city's median single-family home price by its median household income using data from the 2007 third quarter.

Under this equation, it took 10.3 times Honolulu's $63,100 median income to buy a $649,900 median-priced home.

Demographia authors consider a multiple of 3.0 the historical standard of affordability, with anything above that as moderately to severely unaffordable.

Lowest-ranked Los Angeles registered a multiple of 11.5, followed by Salinas at 10.9. The most affordable city was Thunder Bay, Ontario, at 1.8, followed by Youngstown, Ohio, at 1.9.

Some major cities (and their rank/multiple) in the study: Sydney, Australia (216/8.6); Vancouver, British Columbia (213/8.4); city and county of Dublin, Ireland (150/5.4); Auckland, New Zealand (197/6.9); and London (209/7.7).

That Honolulu was one of the least-affordable housing markets comes as no surprise to many observers, given that local median home prices for decades have consistently ranked among the highest — sometimes the highest — in the United States.

In the most recent quarterly report from the National Association of Realtors, Honolulu's third-quarter median home price was fourth highest behind California regions of San Jose-Sunnyvale-Santa Clara, San Francisco-Oakland-Fremont and Anaheim-Santa Ana.

However, the Demographia study showed that home affordability in the United States, where it took 3.6 times the median income to buy a median-priced home, was better than in every other country surveyed except for Canada at 3.1. Multiples were 4.7 in Ireland, 5.5 in the United Kingdom and 6.3 in Australia and New Zealand.

Of 59 "affordable" markets with a multiple of 3.0 or below, all were in Canada and the United States.

"Historic housing affordability has been lost in nearly all markets of Australia, Ireland, New Zealand and the United Kingdom, while the housing affordability crisis is considerably less severe in Canada and the United States," the study said.

The study is a co-production of international public policy consulting firm Wendell Cox Consultancy of St. Louis and New Zealand-based commercial property development and investment firm Pavletich Properties Ltd.

Reach Andrew Gomes at agomes@honoluluadvertiser.com.