Robert Shiller, the economist who famously predicted the U.S. housing bubble, has told CBC News' Neil Macdonald, "I worry that what is happening in Canada is kind of a slow-motion version of what happened in the U.S."

Macdonald writes that Shiller and other economists are most worried about household debt, which has ballooned from 75 percent of household income in 1990, to 150 percent today.

And most of this debt is held by the most "vulnerable households—defined as those devoting 40 percent or more of household income to paying interest charges."