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Additionally, the Romney campaign is releasing a summary of 20 years of taxes, between 1990-2009, detailing their tax expenditures during those years:
In each year during the entire 20-year period, the Romneys owed both state and federal income taxes.
Over the entire 20-year period, the average annual effective federal tax rate was 20.20%.
Over the entire 20-year period, the lowest annual effective federal personal tax rate was 13.66%.
Over the entire 20-year period, the Romneys gave to charity an average of 13.45% of their adjusted gross income.
Over the entire 20-year period, the total federal and state taxes owed plus the total charitable donations deducted represented 38.49% of total AGI.
</blockquote>UPDATE: Here's Mitt and Ann Romney's 2011 tax return: