In the early forties of the 20th century, Western Union has used the first time a commercial intercity microwave transmission system. Another invention of Western Union - time synchronization. July 3, 1884 the company's shares were included in the calculation base for the newly created stock index Dow Jones Transportation Average. One of the common kinds of money transfer is a transfer via the international system of Western Union. In 1884 Western Union has become a joint-stock company and was brought to the stock exchange. The company has entered in the first American stock index Dow Jones.