Denmark’s tax on CO2 passed in 1991 and took effect in May 1992. Fossil fuels are subject to both an energy tax and a CO2 tax. When the CO2 tax passed, it included a subsequent decrease in the energy tax to maintain the overall tax rate. Table 4 shows Danish energy and CO2 tax on various fuel types. The initial tax rate of $16.91 (100 DKK) per metric ton CO2 was reduced to $16.41 (90 DKK) per metric ton CO2 in 2005. With the decrease in the CO2 tax in 2005, the energy tax increased to maintain the overall tax rate (Speck et al. 2006). In 2008, the carbon tax rate remained at $16.41 (90 DKK) per metric ton CO2 emissions (Ministry of Taxation, Denmark 2008). In 2008, the revenues from the CO2 tax were approximately $905 million.