Romney took $4.7 million in itemized deductions and $102,790 in foreign tax credits, which likely represents taxes paid on foreign investments to other sovereign governments.
Romney and his wife, Ann, gave just over $4 million to charity, the campaign said. The amount includes more than $1 million in cash to the Church of Jesus Christ of Latter Day Saints and more than $200,000 to the Tyler Foundation, which serves families of children undergoing treatment for epilepsy. They also reported more than $900,000 in noncash contributions.
But the couple chose to deduct only $2.25 million of their charitable contributions. The reason was "to conform" to Romney's statement last month that he never paid less than 13% in income taxes over the past 10 years, Brad Malt, a lawyer who presides over the Romneys' blind trust, said in a statement.
Indeed, if the Romneys had declared the full $4 million it likely would have pushed their effective tax rate below 13%, said tax attorney Martin Press of the law firm Gunster.
"It is quite unusual for people not to take tax deductions that they're entitled to," Press said.
Tax and accounting giant PriceWaterhouse Coopers, which prepared the Romneys' taxes from 1990 through 2009, issued a letter stating they paid 100% of the federal and state income taxes owed during those 20 years.
The firm also said their average annual effective federal tax rate was 20.2% for the period. And annually, they never paid an effective rate below 13.66%.
PwC did not detail, however, how much Romney made in income during that period or how much he paid in taxes.
Romney has been criticized by both Democrats and even some Republicans for not releasing more than two years' worth of tax returns.
Criticism reached a crescendo when Senate Majority Leader Harry Reid repeatedly claimed, without identifying the source of his information, that Romney hadn't paid federal income taxes for a decade.
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In response, Romney said he never paid less than a 13% effective tax rate in any year over the past decade. He further said the obsession over his tax returns is "small minded."
And the GOP presidential nominee has often gotten flak for having paid a low effective tax rate given his outsized income.
But contrary to popular perception, Romney's effective federal income tax rate is still higher than that of most Americans -- 80% of whom have an effective rate below 15%. That number, however, does not include other federal taxes such as the payroll tax.
The reason Romney's rate is so low -- despite having one of the highest incomes in the country -- is because his income was derived almost entirely from capital gains and dividends from his extensive portfolio of investments. And that form of investment income is typically taxed at just 15%, well below the 35% top tax rate for high earners.