Tax rates could be headed higher starting in January, but for now, April 17 wasn’t too bad considering tax rates on ordinary income, dividends, estates and gifts remain at historically low levels. The tax rate for the 400 U.S. taxpayers with the highest adjust gross income fell nearly 30% in 1995 to just over 18% in 2008, according to the Internal Revenue Service. The federal tax rate for the top 1% of taxpayers dropped 6% to 23% in 2008. The true effective rate for multimillionaires is lower than government statistics indicate because the figures do not include income generated by sophisticated tax-avoidance strategies involving variations of complicated borrowings that never get repaid. The opportunity to avoid, or defer, tax bills is limited only by creativity and the ability to understand complex tax shelters.