How Often Does the S&P 500 Trade Below its 50 DMA?

Given the choppy trading environment that we've been going through recently, the S&P 500 is getting closer to trading at its 50 day moving average.  Since the market has generally been up this year, it hasn't spent much time below that mark.  In fact, out of 195 trading days in 2012, the S&P has only spent 45 days or 23% of the time below its 50 day moving average.  How does that compare to history?    In 65 years of history, the S&P trades below its 50 DMA about 37% of the time.  In 1995 there was only 1 day that it was below the average and in 2008 it spent 195 days below it.