How to create a scatter excel graph with y-axis above and above and below x-axis

Question

I am trying to create an excel scatter plot/line graph that shows y-axis values above and below the x-axis. I am trying to recreate the graph in the link below for the data I have.

I have tried playing around with the primary and secondary axis, but I have not been able to get the secondary axis below the y-axis. It seems like the example graph has one primary axis where the "positive values" for static pressure are in decimal increments and the "negative values" for number of responses are whole numbers. Does anyone have any idea how I can accomplish this? Is it just two excel graphs pasted together with the same x-axis? Any help is much appreciated! Thank you.

Answer 1

What looks like a horizontal axis may not actually be one. Advanced charting tricks in Excel often use helper series to mimic things. In the screenshot below, the Scatter chart has two data series and a helper series that is formatted with a thin black line, markers in the shape of a + character and labels using values from cells. The labels on the actual X axis have been formatted to "None".

There. An X axis in the middle of the chart with custom labels, even.

Likewise, the vertical axis labels can be constructed with a helper series that has all values at X = 0 and Y values calculated to plot where desired, then use labels to mock up the scale. If the scale is wildly different from the actual data plots, you may need to use a conversion factor to ensure the data points end up where they should.

Looking at your example screenshot, it could also be that two charts have been carefully stacked and aligned to appear as one with a middle X axis.