(CNN) - Three-thousand Americans renounced their citizenship and gave up their U.S. passports last year.
That's triple the average for the previous five years, according to an analysis of government data.
It appears taxes might have contributed to the spike.
Unlike most countries, the U.S. taxes citizens on all income, no matter where it is earned or where they live.
And filing taxes is getting more complicated.
One expert says reporting taxes can be so difficult that some are often forced to seek help.
And that can add up to thousands of dollars.
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