dual axes can be good, right? they work here ok https://vis.social/media/lJ0t7qEC9Hx9CS9FhDQ
@tomshanleynz It's not terrible. But could be better, depending on the key message. If we're trying to say x grew faster than y, or the ratio is changing thusly, there are better ways. This is just information, not insight.
For example, I'm a huge fan of what @wisevis has doe to illustrate dual axis as time ribbon scatter plot things. https://excelcharts.com/redraw-troops-vs-cost-time-magazine/