U.S. mortgage rates slipped in the week, the Federal Home Loan Mortgage Corp. said Thursday. Rates for 30-year, fixed-rate mortgages slid from 3.57 percent with an average 0.8 point to 3.54 percent, Freddie Mac said. Rates for 15-year contracts dropped from 2.76 percent to 2.74 percent with an average 0.7 point. 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. Interest rates for five-year adjustable rate mortgages fell to 2.65 percent with an average of 0.5 points from 2.68 percent. One-year adjustable rate mortgages using 10-year bonds as a benchmark, averaged 2.63 percent with 0.4 point in the week, up from 2.62 percent in the previous week.