The International Monetary Fund published a discredited attack on the flat tax last year, which concluded that, “the question is not so much whether more countries will adopt a flat tax as whether those that have will move away from it.” The IMF’s powers of prediction are perhaps even worse than its economic analysis. Since that paper was published, four new nations have a flat tax and several others are about to implement a flat tax. The latest to join the club is Montenegro. Alvin Rabushka, intellectual Godfather of the flat tax movement, explains:

In December 2006, Montenegro’s parliament approved a 15% flat tax on personal income. Effective July 1, 2007, it replaces the previous system of three rates… The new law sets the flat rate at 15% in 2007 and 2008, reduces it to 12% in 2009 and 9% in 2010. Montenegro has set the corporate profits tax rate at 9%, reduced from the previous two-rate system of 15% on taxable profit up to 100,000 and 20% on the gain exceeding 100,000. In 2010, Montenegro will have a unified flat tax of 9% on personal and corporate income. This will be one percentage point less than the 10% unified rate in Macedonia.

Rabhushka’s article also comments on the likely adoption of the flat tax in Albania and East Timor (where the IMF, not surpisingly, is advocating a higher-than-necessary tax rate):

Prime Minister Sali Berisha of Albania secured approval of the Strategic Planning Committee that he chairs for a unified 10% flat tax on personal and corporate income. The proposal has been sent to Albania’s parliament for its consideration. If enacted in a timely manner, the 10% tax on personal income would take effect on July 1, 2007. The proposed 10% flat tax on would slash Albania’s corporate 20% tax in half effective January 1, 2008. …Ramos-Horta plans to transform East Timor into a free-trade nation, with no tariffs, sales tax, or excise taxes save on dangerous substances. He proposes to set personal and corporate income tax rates at the same flat rate between 5 and 10%. His proposal is being drafted into law based on consultations with the World Bank, the United Nations Development Program, academics, and the International Monetary Fund. Although the IMF had pushed for a flat rate between 15 and 20% to prevent East Timor from becoming a tax haven.