Ann Jackson challenged us this week to build this matrix depicting the average worth of customer cohorts during their lifetime.

This challenge involves a mix of LoDs (Level of Detail calculations) and table calculations.

First up , we need to define our customer cohorts (ie group the customers), which for this challenge is based on identifying the quarter they placed their first order in. This will involve an LoD calculation. For a good introduction to LoDs with some worked examples (including a similar cohort analysis example), check out this Tableau blog post.

ACQUISITION QUARTER

DATE(DATETRUNC(‘quarter’,{FIXED [Customer ID] : MIN([Order Date])}))

The 2nd part of the formula in the { … } returns the earliest Order Date associated to the Customer ID, which is then truncated to the 1st day of the quarter that date falls in ie 23 Feb 2019 is truncated to 01 Jan 2019.

For the ‘quarters since birth’ field, we need to calculate the difference in quarters, between the ACQUISITION QUARTER and the ‘quarter’ associated to the Order Date of each order in the dataset.

QUARTERS SINCE BIRTH

DATEDIFF(‘quarter’,[ACQUISITION QUARTER],DATETRUNC(‘quarter’,[Order Date]))

Drag this field into the ‘dimensions’ area of the left hand data pane (above the line if you’re using later versions of Tableau).

Lets sense check what this looks like, by adding

• ACQUISITION QUARTER to Rows (Discrete, Exact Date)
• ORDER DATE to Rows, set to Quarter (quarter year ie May 2015 format which will make a green pill), then set to discrete to change to blue
• QUARTERS SINCE BIRTH to Rows

You can see that while the first row against each cohort starts with a different quarter, the QUARTERS SINCE BIRTH always starts at 0 and counts sequentially down the table.

Next we want to count the number of distinct customers in each cohort, and we’ll use another LOD for this.

CUSTOMERS

{FIXED [ACQUISITION QUARTER]: COUNTD([Customer ID])}

Once again move this field into the Dimensions section of the data pane.

Add this onto the Rows of the above data table, and you should get every row for the same cohort displaying the same number

Add Sales onto Text to get the value of sales made by the customer in each cohort in each quarter. The ‘customer lifetime value’ we need is defined as the total sales so far / number of customers in the cohort.

Remove the QUARTER(Order Date) field from the table, as we’re not going to need this for the display, and it’ll affect the next steps if it’s left.

To get the cumulative sales, we need a Running Total Quick Table Calculation. Click on the Sales pill on the Text shelf and select Quick Table Calculation -> Running Total. The click again and Compute By -> QUARTERS SINCE BIRTH. Add Sales back into the table, so you can see the quarterly Sales value and how it’s cumulating until it reaches the next cohort.

We’ve now got the building blocks we need for the CLTV value we need to plot

Avg Lifetime Value

RUNNING_SUM(SUM([Sales])) / SUM([CUSTOMERS])

Note – I purposefully haven’t called this field what you might expect, as I’m going to ‘fill in the gaps’ that Ann describes in the requirements, and I’ll use that name then.

Pop this field into the table above, again setting the table calculation to compute by QUARTERS SINCE BIRTH

You can now use the data table above to validate the calculation is what you expected.

Now let’s build the viz out.

On a new sheet

• QUARTERS SINCE BIRTH to Columns
• ACQUISITION QUARTER (exact date, discrete blue pill) to Rows
• Avg Lifetime Value to Text, setting the table calculation to Compute By QUARTERS SINCE BIRTH

From this basic text table, you can see the ‘blank’ fields, Ann mentioned. In the data table view, it’s not so obvious. The blank is there because there are no sales in those quarters for those cohorts. To fix we need another table calculation

CUSTOMER LIFETIME VALUE (CLTV)

IF ISNULL([Avg Lifetime Value]) AND NOT ISNULL(LOOKUP([Avg Lifetime Value],-1)) AND NOT ISNULL(LOOKUP([Avg Lifetime Value],1))

THEN LOOKUP([Avg Lifetime Value],-1) ELSE [Avg Lifetime Value] END

This says, if the Avg Lifetime Value field is NULL but neither the previous or the subsequent values are NULL, then use the Avg Lifetime Value value from the previous column (LOOKUP).

Replace the Avg Lifetime Value with the CUSTOMER LIFETIME VALUE (CLTV) field (setting the Compute By again), and the empty spaces have disappeared.

If you hover over the cells in the lower right hand side of the view, you’ll see tooltips showing, indicating that a mark has been drawn on the viz with Null data. To fix this, add CUSTOMER LIFETIME VALUE (CLTV) to the Filter shelf and specify non-null values only to show via the Special tab.

Now if you hover over that area you don’t get any tooltips displaying, as there aren’t any marks there.

Now it’s just a case of formatting the viz a bit more

• Add CUSTOMERS to Rows
• Add CUSTOMER LIFETIME VALUE (CLTV) to the Colour shelf by holding down the Ctrl key then clicking on the field that’s already on the Text shelf, and dragging via the mouse onto the Colour shelf. Using Ctrl in this way has the effect of copying the field including the table calculation settings, so you don’t need to apply them again. This will change the colour of the Text.
• Then change the mark type to Square, which will then fill out the background based on the colour.
• Then edit the colour legend to the relevant palette (which you may need to install via Ann’s link).
• Set the border of the mark via the Colour shelf to white
• Remove the row & column dividers
• Set the row Axis Ruler to a dark black/grey line
• Format the 1st 2 columns so the font is the same and centred. Widen the columns if required.
• Update the tooltip

And then you should be ready to add the viz to your dashboard. My published version is here.

This blog is a bit more detailed that my recent posts, but I’m also conscious I’ve skipped over some bits that if you’re brand new to Tableau, you may not be sure how to do. Feel free to add comments if you need help!

Happy vizzin’! Stay Safe!

Donna