Stacked Bar Chart - Dynamically Set X Axis End Value

I have the following chart:

I'd like to be able to dynanically set the end point of the x-axis to a rounded 5+ hours beyond the largest value displayed based on the filter criteria. So in this example, since the largest downtime hours are 20.77, I'd like the end point to be 25. If the largest was 22.5 then I'd go to an end point of 30 hours and so on.