I had fun with this one, deciding to do a connected scatterplot. There is much debate about the efficacy of connected scatterplots. I agree they require an extra mental leap to comprehend, but once the meaning is grasped, I think they are powerful.
As Hans Rosling proved, they are especially effective when animated, hence the GIF. Following the animation is like following a story, the up/down and left/right movements adding drama and anticipation for the viewer. A static version of the chart is below.
The original this week, on first glance, wasn’t too bad. There’s nothing inherently wrong with a dual axis line chart. However, once you try and work out which axis is which and which colour is which, you realise the creator of this didn’t think through the positioning of the labels!
A simple makeover would have been to fix the labelling and make things much clearer using colour to help the reader. Here’s what that would look like:
I’m happy to concede even that the simpler approach may be better than my connected scatterplot version!