Caterpillar Inc., is an American corporation which designs, manufactures, markets and sells machinery, engines, financial products and insurance to customers via a worldwide dealer network. Caterpillar is the world's leading manufacturer of construction and mining equipment, diesel and natural gas engines, industrial gas turbines and diesel-electric locomotives. With more than US$89 billion in assets, Caterpillar was ranked number one in its industry and number 44 overall in the 2009 Fortune 500. Caterpillar stock is a component of the Dow Jones Industrial Average.