The rise in housing prices over the past several years does not reflect a housing market bubble, according to a new commentary released by the BMO Financial Group Economics Department. Instead, the rise points to strong underlying economic fundamentals.

“It is the case that prices have been showing large increases nationally and in some major urban markets in recent years,” according to Paul Ferley, assistant chief economist, BMO Financial Group. “However, this seems more a reflection of low mortgage rates and still attractive affordability rather than speculative activity.”

The commentary notes four approaches to assessing the presence of a possible housing market bubble: trends in real housing price increases; housing prices relative to rent; housing prices relative to income; and mortgage payments as a share of income. Ferley says that the last approach, mortgage payments as a share of income, provides the strongest evidence that the current situation is not indicative of bubble conditions.

“This measure shows that low mortgage rates are keeping housing very affordable despite housing prices rising faster than income,” says Ferley.

The commentary notes that even if mortgage rates were to rise another 200 basis points, mortgage payments as a share of income would still remain marginally below this historical average.

In Toronto, Montreal, Calgary and Vancouver, mortgage payments as a share of income are currently below the historical average.

However, if mortgage rates rise another 200 basis points as expected by BMO Economics, the measures for both Montreal and Vancouver move above historical averages, although they will remain below this benchmark for Toronto and Calgary.

Vancouver shows a deterioration from an already high share of income allocated to housing. Thus, while no local market is currently showing signs of “bubble market” conditions, Vancouver represents the greatest risk of such conditions emerging.

Ferley cautions that further rapid price gains could jeopardize the benign assessment found in BMO Economics commentary. “The main risk is that interest rates, especially long rates, have provided, and will continue to provide, too much stimulus,” he said. “This could result in housing prices continuing a strong upward trend that move the housing market into ‘bubble’ territory.”

However, such price gains should be held off by the Bank of Canada’s likely course of raising interest rates in the fall, Ferley says.