Interest rates for 30-year, fixed-rate mortgages increased in the United States in the last week, the Federal Home Loan Mortgage Corp. said Thursday.The average 30-year fixed interest rate averaged 6.32 percent with an average 0.7 points on the week ending June 12, compared with 6.09 percent for the previous week, Freddie Mac said.A year ago, 30-year fixed rate mortgages averaged 6.33 percent.At …