Not only has gas gotten cheaper, so have mortgages.
The average rate for a 30-year fixed-rate loan now stands at 3.8%, a rate not seen since May 2013, according to Freddie Mac.
The average 15-year fixed loan, which is popular among those looking to refinance, fell to 3.1%. That rate is about where the 15-year stood in October.
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Rates have been falling in tandem with 10-year Treasury yields, which have also fallen to their lowest level since May 2013, noted Frank Nothaft the chief economist at Freddie Mac.
Plunging oil prices, due to a slowdown in Russia and other global economies, have been sending investors into safe havens like U.S. Treasuries, said Keith Gumbinger, vice president of mortgage information firm, HSH.com.
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"This is again driving down yields and pulling mortgage rates right along with them," he said.
Another factor weighing on rates: few people are seeking loans, said Gumbinger.
Despite the bargain rates, the Mortgage Bankers Association reported a 3.3% decline in the number of people applying for mortgages last week.
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If buyers and existing homeowners seeking to refinance do strike while rates are this low, they can save a lot of money. This week's 0.13 percentage point drop alone results in a $15 a month savings on a $200,000 mortgage balance, or $180 a year.
That's not such a bad Christmas bonus.