A chronology of countries that have adopted a flat tax, indicating the year of adoption, the personal income tax rate, and the corporate income tax rate appears below.
|Flat Tax Jurisdictions|
|Jurisdiction||Year of Implementation||Personal Tax Rate Percent||Corporate Tax Rate Percent|
|Trinidad & Tobago||2006||25||25|
A few comments on the table are in order. All but the first four entries were implemented after the collapse of the Soviet empire, most being former states within the Soviet Union. The spread of the flat tax was contagious, as one country after another enacted flat taxes to maintain competitiveness with neighboring countries to attract both foreign and domestic investment.
The more recent entries in the table have tended to enact very low flat rates, with the modal rate at 10 percent. Thirteen have unified their personal and corporate income rates, with the others maintaining different rates between personal and corporate tax rates.