Federal Estimated Interest Rates
Review the interest rates on overpaid and underpaid federal taxes. 
| Period | Under | Over |
| April 1, 2000 - March, 31, 2001 | 9% | 9% |
| April 1, 2001 - June 30, 2001 | 8% | 8% |
| July 1, 2001 - December 31, 2001 | 7% | 7% |
| January 1, 2002 - December 31, 2002 | 6% | 6% |
| January 1, 2003 - September 30, 2003 | 5% | 5% |
| October 1, 2003 - March 31, 2004 | 4% | 4% |
| April 1, 2004 - June 30, 2004 | 5% | 5% |
| July 1, 2004 - September 30, 2004 | 4% | 4% |
| October 1, 2004 - March 31, 2005 | 5% | 5% |
| April 1, 2005 - September 30, 2005 | 6% | 6% |
| October 1, 2005 - June 30, 2006 | 7% | 7% |
| Beginning July 1, 2006 | 8% | 8% |
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