Adding shading to an excel chart

A couple of possible ideas:

1) This tutorial uses a stacked bar chart to create vertical shaded bands. The main chart is also a bar chart in the tutorial, but it should be fairly straightforward to adapt to a scatter+stacked bar type chart. https://peltiertech.com/Excel/Charts...ticalBand.html

2) This tutorial uses a stacked area chart to create the background effect. https://peltiertech.com/shaded-quadr...scatter-chart/ If you have trouble adapting the previous tutorial, this one might be easier because it starts with a scatter chart.

One of those approaches should adapt to what you want to do.