UBS is the largest financial holding group in Europe, headquartered in Zurich, Switzerland. UBS is currently located in all major financial centres in the world. It has offices in 52 countries. About 34% of its employees work in the Americas, 34% in Switzerland, 18% in other European countries, the Middle East and Africa, and 14% in the Asia-Pacific region. UBS employs about 60,000 people worldwide. At first, there were eight big Swiss banks. After several mergers and reorganizations, especially the two heavyweight "Elephant Marriages" (Credit Bank and People's Bank of China, United Bank and Bank Corporation) in 1993 and 1997, UBS Group and Credit Suisse Group were the only two large Swiss banks. The assets and liabilities of these two banks account for 62% of the total Swiss banking industry, 52.7% of the total employees of the banks, and cover more than 40% of the domestic credit business and nearly 40% of the real estate mortgage business in Switzerland. The main business departments of the bank include asset management, stock trading, foreign exchange trading, precious metal trading, letter of credit, guarantee and financial derivatives trading. Their branches and service networks are all over the world.