Advanced Tableau Reference Lines, Bands, and Distributions

This article will discuss how Advanced Analytics like using Tableau reference lines, bands, and distributions can help you interpret and explain insights from available data. Part of Tableau’s greatness is its ability to make advanced analytics accessible within a few clicks, as we saw with clustering and Quick Table Calcs.  This, in turn, can make you a better, more insightful analyst.  What otherwise would have required complicated Excel formulas or coding knowledge, can be done in a few clicks.  The trick is knowing what’s available to you, when to use it and how to interpret it or explain it to others. 

Tableau Reference Lines Bands and Reference Distributions Explained 

We’ve already examined how adding Tableau reference lines to a chart can provide a lot of insight, highlighting issues like: 

• Are we above or below a desired threshold? 
• What’s the average or median of all these values? 
• Where are the outliers and what should I be paying attention to? 

Similar to Tableau reference lines, Tableau reference bands and Tableau distributions help you take that a step further and see how data falls within certain ranges, rather than just one point. 

Taking Your Tableau Reference Lines Skill to the Next Level with Tableau Reference bands 

1. Create a new Tableau tab and drag Sales to Rows and Product Sub-Category to Columns.  

2. Now click on the Tableau Analytics tab at the top left.  

3. Drag the Tableau Reference Band option onto the chart.  A window will pop up asking if you want it on the Table, Pane, or Cell.  Put it on the Pane option.  
   • The cell option applies to each cell or data point in your Tableau chart (i.e. each bar, or each dot).  The Tableau pane applies to whatever is in the pane, denoted by gray Tableau line dividers.  The Tableau table is the entire table.  For a view with only one dimension, the Table and Pane will result in the same.  But, we’ll add more soon that will make the Pane the more useful choice. 

4. The Tableau reference band window will appear.  Set the Tableau Band From value to be the Average Sales Amount (i.e. change it from Minimum) and leave the Tableau Band to at Maximum. 

5. Set the Tableau Fill color to be the top green color on the bottom color strip.  Click ok. 

6. Sort the Tableau chart in desc order. 

7. Now, drag Customer Segment to Columns in front of Product Sub-Category. 

8. Title the Tableau chart “Above Average Sales by Product Tableau Line.” 

9. Review the Tableau chart for insights that stand out, like the Small Business segment’s sales per product lines are closer together, meaning we can expect all sales to that segment to be more uniform and equal.  Corporate clients, on the other hand, tend to be higher than the other segments in almost every category, but have a much wider span between average and max sales, meaning more variability in purchase behaviors. 

Note: these can be combined with parameters to make them more dynamic and flexible and allow you to control the ranges. 

Tableau Reference Distributions 

Tableau Reference distributions go even further, allowing you to encode multiple values in ranges.  We’ll look at each one using the same chart we just built. 

60, 80% of Total, Percentiles 

1. On the Analytics pane on the left, click Distribution Band and drag it out on top of the chart.  Again, be sure to select Pane from the window that pops up. 

2. The Tableau Reference Distribution box will appear and everything should be defaulted.  Just review it to ensure it’s set to Per Pane, and the value is 60, 80% of average.  

3. On the Tableau Reference Line drop down, make it as dashed lines and changed the color to orange. 

4. Uncheck the box that says “Show recalculated band for highlighted data or selected data points.”   

5. Click ok. 

This chart is showing us the range from Avg. to Max value per Customer segment (created in our previous section) and now it’s also showing us those Tableau product lines that are 60 and 80% of the avg. respectively.  But we don’t really care which Tableau reference lines are 60% of the average; we already know those are performing below average.  We’d rather see which products are within 60 and 80% of the maximums.  With a little focus and effort on those products, we could bring them up closer to our top selling products. 

6. Right click on one of the orange Tableau reference lines.  Choose Edit. 

7. Change the Value to 60, 80% of Maximum by clicking the drop down menu and changing it from Average to Maximum. 

8. Uncheck the box that says “Show recalculated band for highlighted data or selected data points.” 

We can now see which products are close to the top performers.  This is most useful when looking at goal or quota attainment.  We can then see who’s or what is average, what’s below average, and the breakout of our top performers. 

Note: You can also change the percentages from 60 and 80 to whatever you want.  Maybe you want to see the top and bottom 10%, so you could change it from 60, 80 to 10, 90.  Also, while everything there used Percentages, you can also use Percentiles, which work mostly the same way. 

Quantiles 

A Tableau quantile is like a percentage or percentile, but typically a larger segment.  Quantiles are five segments – 20%, 40%, 60%, 80%, and 100%.  Tableau Quartiles are quarters (obviously in increments of 25%), terciles are thirds (increments of 33%), and a decile is 10 cuts, with each segment equaling 10%. I normally leave it at either quartiles (4) or quantiles (5).  Note that these Tableau segments aren’t necessarily equal; they’re dependent on the spread of your Tableau data.  Maybe most of the values fall at the bottom 20%.  The color ranges on your Tableau chart will reflect this. 

1. Right click on the sheet we were just working on Tableau Reference Lines and duplicate it. 

2. Click the Tableau reference band lines on the chart and while holding down your click, drag them off the viz. 

3. Click the Tableau Analytics tab at the top left and then drag out the Distribution Band, set to Per Pane. 

4. Set the Value to Quintiles from the drop down menu. 

5. Change the Number of Tiles from that drop down menu from 4 to 5. 

6. Check the Fill Above and Fill Below box on the right side. 

7. Change the Fill color from the drop down menu to Blue Light. 

8. Finally, check the Reverse box (seen in the image above).  Click ok. 

We now have a color banded Tableau chart, showing the values that fall in the bottom 20% on up. 

Did you enjoy our advanced lesson in Tableau reference lines? We can offer more through our Tableau In-person and online Corporate and Individual training.