Mortgage rates headed in two different directions this week, with fixed-rate instruments plunging and adjustable-rate mortgages soaring.

The average 30-year fixed rate fell 41 basis points from the previous week, to 5.98 percent. A basis point is one-hundredth of a percentage point.

The average 15-year fixed -- a popular option for refinancing -- fell 39 basis points, to 5.46 percent. The average jumbo 30-year fixed fell 17 basis points, to 7.43 percent.

Meanwhile, adjustable-rate mortgages soared. The one-year adjustable-rate mortgage was up a mighty 61 basis points, to 6.14 percent. The benchmark 5/1 ARM was up sharply for the second straight week, rising 23 basis points to 6.44 percent.

Rates have been extremely volatile in recent weeks, sometimes moving a half-percent in a single day. Overall, however, the trend has been higher.

These higher rates have depressed mortgage application activity, which fell for the fifth time in the past six weeks, according to the Mortgage Bankers Association.

For the week ending March 14, mortgage loan application volume fell 2.9 percent on a seasonally adjusted basis.

-- Chris Kissell

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