S&P 500 - 1970

The following graph plots the year-to-date performance of the index for 1970 compared to the probability calculated by a random walk model.

Initial Value: 92.06 Hist. Volatility: 1.06% Annual Drift: 7% Final Value: 92.15 Percentile: 38%
Click on the image for the high resolution version.

The high to date and low to date prices of the stock plotted against a random walk model for 1970 (what's this?).