Data Viz Done Right

July 6, 2010

Easy to see fireworks

2 comments
ChartPorn has once again provided a visualization that is worth improving. The mess created this time is caused by the website Bad Firecracker.

Here are the charts to be critiqued:



I have a couple of big issues with these bar charts:
  1. The grid lines are dark, distracting, horizontal, vertical, and overall incredibly distracting. I think the purpose of the charts is to show a trend, but with all of these grid lines, how are you supposed to see the trend?
  2. The data labels are unnecessary. Again, if you're trying to show an overall trend, the focus needs to be on the trend, not each individual point.
  3. Each chart has a color legend out to the right and it refers to the vertical axis. Why not properly label the axis in the first place? The color isn't needed unless you're showing all of the charts together in one dashboard.
Here's how I would do it:


  1. Show all of the data together so that comparisons can be made.
  2. Since all of the data is on one chart, use colors to differentiate the measures.
  3. For the purpose of comparing their charts to mine, I created bar charts. What you will notice though is that there are no distracting grid lines and no data labels.
  4. The axis titles clearly indicate what data is displayed
  5. Only show the year once, at the bottom of the chart.
  6. A data table is at the bottom so that if someone is interested in knowing the exact number, they can quickly look it up. This allows the data labels to be removed from the chart.
Surely you see that I have line charts to the right of the bar charts. I prefer the line charts to the bar charts because they're easier to read and the data-to-ink ratio is low.

Follow these simple principles as you create your charts. Your readers will thank you. Keep it simple.

2 comments :

  1. Thanks for the additional perspective Joe. Would you hide the year 2000 in the % from 1st charts? This would keep the results from starting at 0.

    ReplyDelete