In the early forties of the 20th century, Western Union has used the first time a commercial intercity microwave transmission system. 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 April 1851 companions registered in Albany New York and Mississippi Valley Printing Telegraph Company (NYMVPTC), which included founded two years before New York State Printing Telegraph Company. In October 2006 the company made an initial public offering of shares on the New York Stock Exchange, becoming independent from First Data company. In 2007 the company made 167.7 million transactions on money transfers between individuals and 404.6 million transactions between physical and legal persons.