According to the cross-Canada survey data that I mentioned earlier, it's estimated that across Canada 7% of homes have high levels of radon, but that varies quite significantly across the country. In Manitoba and New Brunswick, it was over 20%, but in every single province there were regions where 10% to 20% and in some places 40% to 50% of homes tested high. The average across the country at 7% of homes is still very significant.
On June 18th, 2015. See this statement in context.