It's funny how jargon and charts can combine to tell a story (or not, as the case may be)....
The above chart shows the "impact" of WSB on attendance. Not sure what WSB is, but it makes a huge impact in 2013 -- right???
Upon looking at the web site and digging deeper, WSB is "Walking School Bus".
What's "wrong" with this chart?
- Non standard y-axis - 89.0 to 93%
- Unnecessary precision (92.8% anyone)
- WSB not defined
The non standard y-axis makes it look like a huge difference in 2013 between WSB and No WSB - but actually it's 1.7% - based on the school with approximately 150 learners (small Primary school) this translates to about 2 - 3 learners. So is the difference meaningful -- probably not, but it sure looks it.
A better visualisation of the graph would be:
Can we say WSB makes an impact - errr, no.
Call to action
- Be careful with using non standard axis - they can manipulate the visualisation (of course that might be what you want)
- Don't use acronyms that aren't defined on the chart
- Don't use gridlines
- If you use data labels, don't add too much precisions