Forum Discussion
Excel graphs
Afraid there is no straightforward solution for adding filled/shaded boxes. Workaround techniques are here
Shaded Quadrant Background for Excel XY Scatter Chart - Peltier Tech
Fill Under or Between Series in an Excel XY Chart - Peltier Tech
Don't miss comments to above if you go such way, they could be quite useful.
SergeiBaklan , speaking of workarounds, at the moment of quick need at work, too much "tricky" workarounds may not be possible to implement due to need to search the trick or not much time available amid busy work. How is this one? It is imperfect but fast to recall and implement, perhaps(?)
That's TheAlbinodonkey shall decide if solution meets his needs.
Reminds me drawing the polygons in Excel with bunch of points and quite bad performance. But that could be, why not.