U.S. mortgage applications jumped to their highest level in more than 2-1/2 years last week, led by a surge in refinancing activity, as some home borrowing costs tumbled to their cheapest level since September 2017, the Mortgage Bankers Association said on Wednesday. The Washington-based group’s seasonally adjusted index on loan requests, both to buy a home and to refinance one, increased by 26.8% to 529.8 in the week ended June 7, which was the highest since September 2016. Interest rates on 30-year fixed-rate “conforming” mortgages, or loans whose balances are $484,350 or less, decreased to 4.12%, the lowest level ... (full story)