While investors are no doubt wringing their hands over what’s going on in the stock market this week, here’s another thing to fret over: rising mortgage rates.

“What many in 2016 thought would never happen again is now reality,” writes Wolf Richter of the Wolf Street blog. “A line in the sand has been breached.”

He explained that the average interest rate for 30-year fixed mortgages with conforming loan balances ($453,100 or less) and a 20% down-payment just passed 5% — the highest since 2010, according to the Mortgage Bankers Association.

This, however, is not quite the “pain threshold” for the housing market, Richter wrote. No, that number is 6%, but that rate is moving ever closer.

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