The author presents evidence that the money supply has a major effect on GDP and stock prices. This conclusion is drawn from observing the effect on nominal GDP (for which the proxy is M2 or equivalent) and the stock market (for which the proxy is the S&P 500 Index) during three notable boom/bust periods in the United States and Japan. All three of these time periods were sparked by significant technological change and exhibited a long period of economic growth followed by an economic decline and stock market crash. He concludes that the subsequent economic and market recovery is directly correlated to the monetary policy during the post-boom period.