“I would conclude that correctly analyzing Fed moves is much more important than stock picking,” said Brian Kelly of Shelter Harbor Capital. “If you want to generate alpha, you should trade the stock market 24 hours before an FOMC meeting. Simply follow the trend for that 24 hours and you will outperform.”

The chart shows the effect to be significantly pronounced in the aftermath of the tech bubble when Greenspan re-inflated stock and housing prices by slashing rates. It widens even further in the period since the financial crisis of 2008 as the market became beholden to the Fed’s use of its balance sheet to add liquidity to the market.

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“Blame Greenspan for this S&P 500 effect… it’s his free put,” said Robert Savage, chief executive of research site Track.com and formerly managing director of FX Macro Sales at Goldman Sachs. “Since 1994, the battle of central banks hasn't been to fight inflation, but rather to smooth out the business cycle and credit. The convergence of global rates and inflation left the decisions of the FOMC as the key variable for S&P 500.”

The market is down six days in a row currently on the concern that the Federal Reserve will not embark on its third round of so-called quantitative easinganytime soon. Minutes from the central bank’slast meeting, released Wednesday, reinforced the concern that the economy is muddling along enough to keep the Fed on the sidelines.

To be sure, one cannot look at these Fed actions in a vacuum and conclude the S&P 500 would plummet 50 percent if the Fed were to undue all of its supportive measures of the last two decades. But that doesn’t mean this exercise can’t be instructive.

For example, proponents of index funds will often argue their case by using data that shows a significant drop in S&P 500’s yearly returns if you took out the five best days of that particular year. The point: you need to always be fully invested so you don’t miss one of those days, which account for the majority of the market’s annual return.

The Fed’s next announcement is due August 1st and it would seem by this study, one would want to make sure they are invested in the market by 2pm on July 31st,



“It's a QE world,” said Josh Brown, an investment advisor and popular author of The Reformed Broker blog. “We're all just trading in it.”

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