How do you calculate the M1 money supply?
You actually don't need to calculate the M1 money supply because the Federal Reserve reports it regularly. It's defined slightly differently for different countries, but if you want to try to calculate the M1 money supply of the United States, it's pretty simple.
When you're determining the M1 money supply, start with the bills and coins in circulation and add the value of the deposit accounts that are considered liquid at regular banks, including checking and savings accounts, negotiable order of withdrawal (NOW) accounts, and credit union share draft accounts. Traveler's checks should also be added to this equation.