(EY) is a multinational professional services firm based in London. It was the third largest professional services firm in the world by aggregated revenue in 2012 and is one of the Big Four audit firms. The organisation has 190,000 employees and more than 700 offices in over 150 countries. It provides financial auditing, tax, consulting and advisory services to companies. The firm dates back to 1849 with the founding of Harding & Pullein in England. The current firm was formed by a merger of Ernst & Whinney and Arthur Young & Co. in 1989 and was known as Ernst & Young until 2013, when it underwent a rebranding to EY.