S&P 500 - 1982

The following graph plots the year-to-date performance of the index for 1982 compared to the probability calculated by a random walk model.

Initial Value: 122.55 Hist. Volatility: 1.24% Annual Drift: 7% Final Value: 140.64 Percentile: 67%
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 1982 (what's this?).