Long-term U.S. mortgage rates dropped in the week ending Thursday in part due to low inflation, the Federal Home Loan Mortgage Corp. said. "Mortgage rates were flat to down a little this week amid reports that inflation remains subdued. The Consumer Price Index was up to 0.3 percent in December after being unchanged in November. For the year as a whole, consumer prices rose just 1.5 percent in 2013," said Freddie Mac Chief Economist and Vice President Frank Nothaft in a statement. Rates for 30-year, fixed-rate mortgages slipped from 4.41 percent to 4.39 percent with an average 0.7 point in the past week. Rates for 30-year, fixed-rate mortgages averaged 3.42 percent a year ago. Rates for 15-year, fixed-rate mortgages slid from 3.45 percent to 3.44 percent with an average 0.7 point in the week. A year ago in the same week, 15-year, fixed-rate loans averaged 2.71 percent. Among the shorter-duration loans, rates for five-year Treasury-indexed, hybrid adjustable-rate mortgages averaged 3.15 percent this week, with an average 0.5 point, up from a week ago when interest averaged 3.1 percent. A year ago, they averaged 2.67 percent. Rates for one-year, Treasury-indexed, adjustable-rate loans averaged 2.54 percent in the week with 0.5 points, down from last week's average rate of 2.56 percent. Last year over the same period, rates for one-year, adjustable-rate loans averaged 2.57 percent. One point is equal to 1 percent of the amount of the loan and is typically paid up front. It includes a corresponding discount on the loan's long-term interest rates.