Data Viz Done Right

September 27, 2017

Workout Wednesday: Are the contributions of top sellers increasing throughout the year?

This week we delve into some tricky calculations for Workout Wednesday week 39. My goal for this analysis was to understand:

  1. How much the maximum selling product sub-category accounts for in a given month.
  2. How much that contribution has changed throughout the year.

The idea being that you would hope that irrespective of WHICH sub-category is the top selling, the contribution of the top selling product would remain steady. It's generally not good for one sub-category to account for too much in sales because then it could be a sign that you need to diversify. (Correct me if I'm wrong please).


  1. The line chart shows how the contribution of the top selling sub-category within each month has changed since January. That means you'll need to first figure out the value of the top selling category, then figure out the contribution of that sub-category within each month, then figure out how that contribution has changed compared to January within each year.
  2. Label the ends of each line. The label need to be right-justified horizontally and center-justified vertically. The label MUST NOT overlap the line at all.
  3. Match the format of my numbers.
  4. Match the tooltips.
  5. Match the title (easy peasy, just write what I wrote).
  6. Product categories are listed down the left.
  7. Years and Months are listed across the view. 
  8. Month labels are hidden.

Download the data here.

If you have any questions, let me know. Please tweet a picture of your attempt, include a link to the viz on Tableau Public and be sure to tag @EmmaWhyte and @VizWizBI.

Good luck!!


  1. i am woundering whether there is a possibility to see, what is the max selling Sub-Category?

  2. Andy,
    I'm unable to understand the second part of the tooltip, which says sales are +x% compared to month,year

    1. You can download the workbook to see how I created it.