Graphs in BI Publisher

I'm working on a repeating graph and need a fixed Y-axis and fixed X-axis. The Y-axis are numeric values and I've succeeded in establishing the min and max values that I want for it. The X-axis is dates as strings. These are written as 06/07/16. A want for it a range of 03/31/12 to 06/30/16. It's a long range, 4 years and 3 months. Ideally I would like one other date in the middle on that range, so that the axis has three labels: 03/31/12 at the far left, 05/16/14 in the middle, and 06/30/16 at far right. The data