Uneven spacing when dragging x-axis

[jay60]

When dragging the x-axis it's very smooth to where you can expand/contract the chart 1 bar at a time. But when you do this with your pointer within about 2cm of the y-axis(full screen size chart)the bars jump 4 or 5 at a time. And the closer you get to the y-axis the more you lose control.

Jay