In the 30's of the twentieth century, Western Union has become the world's largest telegraph company. Another invention of Western Union - time synchronization. In 1866, Sibley ordered the engineers to develop a Western Union telegraph system of stock quotes in real time. In 1914 Western Union engineers invented the first payment card - a prototype of the modern credit card. Western Union made so that the time in all of American civil services was the same. Number of active holders of "Golden Card" of Western Union amounted to 9.5 million people worldwide. 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.