Mortgage interest rates have fallen so rapidly this year that tens of thousands of households have rushed to refinance, which not only lowers monthly payments but has a secondary serendipitous effect - reducing mortgage delinquencies.

The Mortgage Bankers Association found that delinquency rates on residential mortgages fell from 4.47 percent in the first quarter this year to 4.33 percent in the second quarter.While that doesn't seem like much of a change, it actually is good news for many people - 63,000 fewer households are delinquent in the second quarter than in the first.

"A combination of robust economic growth, heavy refinancing activity and a slowdown in the number of upward interest-rate adjustments on ARMs were the primary factors contributing to the improved delinquency situation," MBA executive vice president Paul Reid said this week.

"In particular, the wave of refinancing activity in the first half of the year has helped reduced mortgage debt-service payments as a percentage of disposable personal income to near 15-year lows."

The mortgage bankers also reported that refinancing accounted for more than half of all mortgage loans last week (Sept. 4), up from 45 percent the previous week.

And there's no end in sight. The national average for a 30-year mortgage fell to 6.77 percent this week, down from 6.82 percent last week, according to Freddie Mac.

"Not only have mortgage rates fallen to historical lows, they have remained at such levels (below 7 percent) for a record-breaking 13 weeks," said Robert Van Order, chief economist for Freddie Mac. "The real news, however, is that they may very well average out even lower next week."

Rates are falling rapidly because with the scary turmoil in the stock market, investors are moving their money to the relative safety of bonds. Bond rates directly affect mortgage rates since mortgages are bundled together and sold competitively in the financial marketplace.

If you haven't refinanced yet, consider looking at mortgage rates in the next week or so. In markets with multiple lenders you will be able to find rates below the national average with perhaps one point or less.

How much can you save? If you have a $130,000 mortgage with an interest rate of 8 percent, you're paying $953 a month in principal and interest. Reduce that to $844 a month with a rate of 6.77 percent. Or, if you're lucky, to $821 a month with a rate of 6.5 percent.

Or, cut your total interest by gobs with a 15-year mortgage. At a rate of 6.4 percent on a principal of $130,000, the monthly payment would be $1,125, or $217 more than you would be paying on a 30-year loan at 8 percent.

With all that money saved on refinancing, furnish a home office. An American Express survey finds 26 percent of households earning $40,000 or more a year are planning to add or refurnish a home office this year.

"On average, homeowners expect to spend $1,459 equipping their new work area," American Express said.

The most popular purchase (also one of the least expensive) is a desk chair, which 39 percent plan to buy. But 33 percent also plan a more costly purchase - a home computer - and 30 percent a fax machine

Other planned purchases, in descending order of popularity, are a work station, desk accessories, a desk, a phone or answering machine and cabinets and file storage units.