Mortgage rates fell sharply this week, with 15-year-fixed mortgages falling below 5 percent.

The average 30-year fixed-rate sank 31 basis points, to 5.33 percent. A basis point is one-hundredth of a percentage point. This week's rate is just a few basis points higher than the lowest rate ever recorded in the Bankrate weekly survey -- 5.28 percent on June 11, 2003.

The average 15-year fixed -- a popular option for refinancing -- plunged 31 basis points, to 4.85 percent. That marks the lowest rate since March 2004.

The average jumbo 30-year fixed slid 23 basis points, to 6.91 percent.

Adjustable-rate mortgages were split. The one-year adjustable-rate mortgage ticked up1 basis point, to 5.98 percent. The popular 5/1 ARM dropped 14 basis points, to 5.72 percent.

Mortgage activity fell a seasonally adjusted 8.2 percent for the week ending Jan. 2, according to the Mortgage Bankers Association.

Refinancing activity slid 12.3 percent from the previous week, while applications for new purchase actually grew 7.3 percent, according to the MBA.

This week's numbers included an adjustment for the New Year's Day holiday.

Meanwhile, pending home sales plunged during November to their lowest levels in seven years.

Sales fell 4 percent for the month when compared with October, according to the National Association of Realtors Pending Home Sales Index. The index reading was based on contracts signed in November.

This month's reading -- 82.3 percent -- was also 5.3 percent below the reading for November 2007 and is the lowest since the series started in 2001.

-- Chris Kissell

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