The chart above shows the rolling returns for stocks and gold.
Catherine Mulbrandon of Visualizing Economics writes:
For the period 1928-2013, the average annual compound real return of stocks = 6.3% and gold = 2.0%. However, the price of gold was controlled by the government until the mid-70s when the US finally abandoned the gold standard. For the period 1976-2013, the average returns were stocks = 7.2% and gold = 2.0%.