When we have a vertical bar graph which has the sum percentage above each bar, some of the percentage labels are disappearing. This happens to the top-most labels, like bars taller than the 80% mark (example). It is not a question of the height of the graph itself; we can increase the height and the percentages still do not show up. Other percentages at the top of bars like 70% or 34% show up fine, only the tallest ones do not...Any thoughts as to the cause of this behavior? Thanks!