After peaking at 40.8 million in 2007, the number of tax returns claiming the mortgage interest deduction has steadily fallen, and as of 2013, the latest year from which data is available, stands at just 33.3 million. Not surprisingly, the amount of mortgage interest paid also peaked in 2007 at $491 billion and is now $296 billion, while the average amount of MID claimed/filer has fallen from $12,052 to $8,900.