The Toyota Prius (/ˈpriːəs/) is a full hybrid electric mid-size hatchback, formerly a compact sedan developed and manufactured by Toyota. The United States Environmental Protection Agency and California Air Resources Board (CARB) rate the Prius as among the cleanest vehicles sold in the United States based on smog-forming emissions. The Prius first went on sale in Japan in 1997, and was available at all four Toyota Japan dealerships, making it the first mass-produced hybrid vehicle. It was subsequently introduced worldwide in 2000. The Prius is sold in over 90 markets, with Japan and the United States being its largest markets. Global cumulative Prius liftback sales reached the milestone 1 million vehicle mark in May 2008, 2 million in September 2010, and passed the 3 million mark in June 2013. Cumulative sales of 1 million Priuses were achieved in the U.S. by early April 2011, and Japan reached the 1 million mark in August 2011. Global sales of the Prius c variant passed the 1 million mark during the first half of 2015.