The reason for looking back several years to report the IRA to Roth conversion is because of the five-year rule.
Roth IRA Conversions: The 5 year rule on conversions determines whether you’ll pay the 10 percent penalty when you withdrawal the amount you converted.
Roth IRA Contributions: While you can withdraw contributions tax and penalty free, the 5 year rule on contributions determines whether you’ll owe ordinary income tax on the earnings from the contributions.
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