TerraForm Power Inc - 2017  (Inactive Symbol)

The following graph plots the year-to-date performance of the stock for 2017 compared to the probability calculated by a random walk model.

Initial Value*: $12.8 Hist. Volatility: 4.14% Annual Drift: 7% Final Value*: $12.2 Percentile: 59%
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 2017 (what's this?).