Almost all countries in the world have phased out automotive leaded fuel. In 2011, six countries were still using leaded gasoline: Afghanistan, Myanmar, North Korea, Algeria, Iraq, and Yemen. It was expected that by the end of 2013 those countries, too, would ban leaded gasoline, but this target was not met. Algeria replaced leaded with unleaded automotive fuel only in 2015. Different additives have replaced the lead compounds. The most popular additives include aromatic hydrocarbons, ethers, and alcohol (usually ethanol or methanol). For technical reasons, the use of leaded additives is still permitted worldwide for the formulation of some grades of aviation gasoline such as 100LL, because the required octane rating would be technically infeasible to reach without the use of leaded additives.