In case you still thought stock prices were advancing on improving economic growth, take a gander at this puppy. The grey line is the Fedโ€™s securities holdings. You know โ€“ all the Treasuries (and MBS) the Fed is buying from Wall Street with freshly printed money. The black line is the S&P 500. Quite a correlation wouldnโ€™t you say? The question that savvy investors should be asking themselves is, โ€œWhat happens when the Fed stops buying bonds in June?โ€ It could be an unpleasant summer for the unprepared.ย