Questar Corporation - 2008  (Inactive Symbol)

The following graph plots the year-to-date performance of the stock for 2008 compared to the probability calculated by a random walk model.

Initial Value*: $13.8 Hist. Volatility: 1.56% Annual Drift: 7% Final Value*: $8.4 Percentile: 7%
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 2008 (what's this?).