Data Viz Done Right

# Makeover Monday: How Much Has the Cost of Christmas Dinner Really Risen?

Well, this is it! 52 weeks of Makeover Monday under our belts. Thank you for an incredible year and for participating in this amazing project.

In case you missed it, Makeover Monday will continue in 2017. Eva Murray and I have big plans in store for everyone. If you ever have questions, comments or feedback, give us a tweet.

Ok, so onto week 52. The BBC published an article early in December about the cost of Christmas dinner in the UK with this blaring headline:

# Christmas dinner costs 'rise 14%'

Inside the article were these basic charts:

Fortunately, Andy C was able to locate the data on BBC Github. Let’s review the charts.

What works well?

• A line chart is a good choice for showing change over time.
• The line chart uses about a 3x2 ratio which doesn’t distort the shape too much given the axis is zoomed in.
• The bar charts work fine for comparing the two years.

What doesn’t work well?

• The line chart has smoothed curves, which lead you to believe there were changes throughout the year, but the data is only at the yearly level. This could be misleading.
• What food are included? The data on Github doesn’t match the data in the chart? How are we to know what they consider to be the Christmas foods?
• There’s no logical sort to the bar chart. It’s neither sorted by 2015 nor 2016. I can’t make out how it’s sorted.
• The bar chart doesn’t include all foods they have data for, so why did they only show these foods? Are these the foods that comprise the line chart? We have no way of knowing.
• Were the Christmas themed colors in the bar chart intentional? If so, I get why they did it, but it won’t work for their colour-blind readers.
• The title of the bar chart indicates it’s about the price change, but they make the reader do the change maths in their head. Why not just show the change?
• Why are they comparing 2016 to 2015 and not a different year? That seems a bit shortsighted and sensationalist to me.

For my version, I thought it was important to:

1. Indicate when the peak price occurred
2. Show the entire time period to get a better sense for the rate of change
3. Indicate whether the 2016 price has increased or decreased compared to 2006
4. Sort the products by the 2016 price
5. Show the rate of change and the latest price
6. Optimise the view for mobile

Given these ideas above, here is my last Makeover Monday for 2016. I’m looking forward to continuing this project with Eva in 2017.