Among those 46 million, 34.4 million deducted $328 billion for mortgage interest and 39.2 million deducted $172 billion in real estate taxes.
The most recent detailed tax information available is from tax year 2012. In that year, Americans had $9.1 trillion in adjusted gross income and $6.4 trillion in taxable income. We paid $1.2 trillion in income taxes.
Deductible expenses include state and local income and property taxes, mortgage interest, charitable contributions, and a handful of other items.
The difference between adjusted gross income and taxable income is largely in deductions and exemptions.
97 million tax filers took a standard deduction, meaning they subtract a flat dollar amount from their income for various living expenses.
46 million tax filers took itemized deductions instead, meaning they subtract actual amounts spent on deductible expenses from income.
At the average tax rate, these real estate deductions helped tax payers save roughly $100 billion in 2012.