"Relying on government statistics to track the fundamentals of the economy is a lot like driving by looking in the rear view mirror—and a foggy one at that. The data comes with an unavoidable and sometimes significant delay, it is often manipulated and estimated, and many series are subject to substantial revision long after the fact. That's why it can be more rewarding to watch market-based indicators (i.e., prices), since they reflect real-time information, and they incorporate the collective knowledge and decisions of hundreds of millions of economic actors with access to every conceivable piece of information."
in Calafia Beach Pundit
Related: SPDR S&P 500 ETF (NYSE:SPY), ProShares UltraShort S&P500 (ETF) (NYSE:SDS), iShares Russell 2000 Index (ETF) (NYSE:IWM), SPDR Dow Jones Industrial Average ETF (NYSE:DIA)