S&P 500 - 2007

The following graph plots the year-to-date performance of the index for 2007 compared to the probability calculated by a random walk model.

Initial Value: 1418.3 Hist. Volatility: 0.56% Annual Drift: 7% Final Value: 1468.36 Percentile: 40%
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 2007 (what's this?).