Thanks @mike and @j-f1. I like your ideas.
I just realized that the axis in question for my problem is the x-axis – which would not lend itself well to the “Styled Axes” option Mike proposed. But I did benefit greatly by looking at the formatting code. I think we’ll probably end up going with the journals recommendation (whatever that might be) but I’d like to be in a position to recommend something. Still looking for some references on the subject.
Another related issue is how to format the corresponding values in a hover-over/tooltip. Typically, I’d use the same formatting as the x and y-axis but not sure if we have the room to spell out “millions” etc.
No response needed – except if you happen to come across an academic reference to a best-practice/standard.