I need to 1. The top of your y-axis scale should end at 100% because that represents a maximum possible value. 2. On your x-axis scale, it would be cleaner to label numerically (1-22 if my count is correct). You can label the axis as Day or Session. 3. Place a vertical dotted line between the point where the curriculum changed as you suggest. Label the third condition something that reflects the change DRA with Increased Task Difficulty.
Solved by S. J. in 19 mins