As of February 2015, the M1 money supply in the United States was $2,988.20 billion. This is based on figures reported by the Federal Reserve. M1 has fluctuated over the past few decades, as expected. At the beginning of the 2015 calendar year, for example, M1 was calculated at $2,924.20 billion. Between 1959 and 2015, the M1 supply averaged $818.62 billion. The February 2015 numbers represent the highest amount of money ever in M1. The lowest values for M1 existed in January 1959, with $138.90 billion. The Federal Reserve tracks values for M1 as well as other categories of the money supply, such as M2. The Federal Reserve also tracks other banking information such as private loans, bank balance sheets and foreign bond investments. Tracking the money supply is essential in order for the Federal Reserve to establish and make changes to monetary policy. The money supply ultimately affects interest rates that affect consumers as well as small-business investors.
Money supply, also known as money stock, is divided into several categories, each designated by the letter "M" and followed by a particular number, such as "1," "2" and so forth. M1 in the U.S. consists of all currency, both paper notes and coins; demand deposits; traveler's checks and other accounts available for deposit. In general, it includes money in the form of cash and that which is held in checkings and savings accounts. Traveler's checks function like cash, so these easily fit into the category of M1 as well.