The CBA does collect data on mortgages in arrears. The mortgages-in-arrears rate right now is 0.28%. What that means is that about 1 in 350 mortgages is in arrears. You can compare that to the financial crisis, when that number went up to about 0.45% in Canada around 2008. In comparison, in the United States that figure went up to above 5%, which is 11 times that figure, which I think demonstrates the differences between the Canadian and U.S. markets.
If you go back further, you'll see that the mortgages-in-arrears rate has gone no higher than 0.65% nationally. There are some regional variations, but nationally that figure has been no higher than 0.65%.