The Federal Home Loan Mortgage Corporation announced that the interest rate on the average 30-year fixed loan across the country is now 8.93% -- up nearly two percentage points from a year ago and up from 8.89% just seven days earlier. It's the highest rate since April 1992. Despite rising rates, home sales have remained robust recently. One reason is that homebuyers are increasingly choosing adjustable rate mortgages -- at about double the pace of last year. The introductory "teaser" rate on new ARMs is still below 6% nationwide, on average, and individual banks in many areas are offering terms as low as 4% to 5%.