Long Term Chart of S&P 500 Priced in Gold

The great team over at the St. Louis Fed has finally added historical gold prices into the FRED database.  This allows us to now create great long term charts like the one below--the S&P 500 priced in gold ounces since 1968.  To the extent that one believes that gold is a useful ruler for measuring value, this chart should be an important one.  The S&P 500 is cheaper in gold terms than it was in 1968, but still isn't quite as cheap as it got in 1980 when it sold for just 0.17 ounces of gold.