NASDAQ Composite Index - 1997

The following graph plots the year-to-date performance of the index for 1997 compared to the probability calculated by a random walk model.

Initial Value: 1291.03 Hist. Volatility: 0.77% Annual Drift: 7% Final Value: 1570.35 Percentile: 82%
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 1997 (what's this?).