Vision Chart, X-Axis based on samples not time

We have an Ignition Edge 8.0 system. We have a tag with history, on change logging, with 0 deadband.

I want to chart the last 20 values of this tag. I can easily figure out how to make a chart with time on the x-axis, but not have the last few samples on the x-axis.

Is this possible? I thought I had it with a ‘count’ axis in the classic chart, but that was just date in a different format.