Compute using (table across, down) in Tableau - Dashboard Guide

Dashboard Mode - Compute using (table across, down)

Business Question

How can we analyze monthly sales trends by computing running totals across months and cumulative totals down product categories using Tableau's Compute Using feature?

Sample Data

Product Category	Month	Sales
Furniture	Jan	100
Furniture	Feb	150
Furniture	Mar	200
Office Supplies	Jan	80
Office Supplies	Feb	120
Office Supplies	Mar	160
Technology	Jan	200
Technology	Feb	250
Technology	Mar	300

Dashboard Components

• KPI Card: Total Sales
  Formula: SUM([Sales])
  Result: 1560 (sum of all sales)
• Line Chart: Running Total of Sales Across Months
  Calculation: RUNNING_SUM(SUM([Sales]))
  Compute Using: Table (Across)
  Explanation: Calculates cumulative sales month by month across all categories combined.
  Example values:
  Jan: 380 (100+80+200), Feb: 900 (380+150+120+250), Mar: 1560 (900+200+160+300)
• Bar Chart: Cumulative Sales Down Product Categories
  Calculation: RUNNING_SUM(SUM([Sales]))
  Compute Using: Table (Down)
  Explanation: Calculates cumulative sales category by category for each month.
  Example for Jan:
  Furniture: 100, Office Supplies: 180 (100+80), Technology: 380 (180+200)
• Table: Sales by Product Category and Month
  Shows raw sales data for reference.

Dashboard Layout

+----------------------+-----------------------------+
|      Total Sales      | Running Total Across Months  |
|      (KPI Card)       |         (Line Chart)         |
+----------------------+-----------------------------+
| Cumulative Sales Down |       Sales Data Table      |
|   Product Categories  |                             |
|      (Bar Chart)      |                             |
+----------------------+-----------------------------+

Interactivity

Filters on Month or Product Category update all components simultaneously:

• Selecting a specific month updates the running total and cumulative sales to reflect only data up to that month.
• Choosing a product category filters the sales data table and updates the cumulative sales bar chart to show only that category's cumulative sales.

Self Check

If you add a filter to show only February and later months, which components update and how?

• Total Sales KPI: Updates to sum sales from Feb and Mar only (150+120+250+200+160+300 = 1180).
• Running Total Line Chart: Starts cumulative sum from Feb onward.
• Cumulative Sales Bar Chart: Shows cumulative sales down categories for Feb and Mar only.
• Sales Data Table: Displays only rows for Feb and Mar.

Key Result

Dashboard showing total sales, running totals across months, and cumulative sales down product categories using Tableau's Compute Using feature.

Practice

1. In Tableau, what does setting Compute Using: Table (Across) do to your calculation?

easy

A. Calculates values only for the first column in the table.

B. Calculates values moving top to bottom down rows in the table.

C. Calculates values moving left to right across columns in the table.

D. Calculates values based on the entire table without direction.

Solution

1. Step 1: Understand 'Compute Using' concept

   'Compute Using' defines the direction Tableau uses to perform calculations across the data layout.

2. Step 2: Identify what 'Table (Across)' means

   'Table (Across)' means calculations move horizontally from left to right across columns.

3. Final Answer:

   Calculates values moving left to right across columns in the table. -> Option C

4. Quick Check:

   Table (Across) = left to right calculation [OK]

Hint: Table (Across) means calculation moves left to right [OK]

Common Mistakes:

• Confusing 'Table (Across)' with 'Table (Down)' direction
• Thinking it calculates vertically instead of horizontally
• Assuming it calculates over the entire table without direction

2. Which of the following is the correct way to set a table calculation to compute using 'Table (Down)' in Tableau?

easy

A. Drag measure to Rows shelf and select 'Table (Across)'.

B. Right-click measure > Edit Table Calculation > Select 'Table (Down)' in Compute Using.

C. Use the filter shelf to set Compute Using to 'Table (Down)'.

D. Double-click the dimension and choose 'Compute Using Table (Across)'.

Solution

1. Step 1: Locate how to edit table calculation

   Right-click the measure with the table calculation and choose 'Edit Table Calculation' to access Compute Using options.

2. Step 2: Select 'Table (Down)' option

   Within the dialog, select 'Table (Down)' to compute calculations moving top to bottom down rows.

3. Final Answer:

   Right-click measure > Edit Table Calculation > Select 'Table (Down)' in Compute Using. -> Option B

4. Quick Check:

   Edit Table Calculation > Choose Table (Down) [OK]

Hint: Edit Table Calculation to set Compute Using direction [OK]

Common Mistakes:

• Trying to set Compute Using from filter or dimension menus
• Confusing 'Table (Across)' with 'Table (Down)'
• Not right-clicking the measure to edit calculation

3. Given a table with sales data by Region (rows) and Month (columns), if you set a running total calculation with Compute Using: Table (Down), what will the running total do?

medium

A. Calculate running total down regions for each month vertically.

B. Calculate running total over the entire table ignoring layout.

C. Calculate running total across months for each region horizontally.

D. Calculate running total only for the first month.

Solution

1. Step 1: Understand table layout and Compute Using

   Rows represent Regions, columns represent Months. 'Table (Down)' computes vertically down rows.

2. Step 2: Apply running total with 'Table (Down)'

   Running total sums values moving down each column (month) across regions.

3. Final Answer:

   Calculate running total down regions for each month vertically. -> Option A

4. Quick Check:

   Table (Down) = vertical running total per column [OK]

Hint: Table (Down) runs calculation vertically down rows [OK]

Common Mistakes:

• Thinking running total moves across months horizontally
• Assuming calculation ignores table layout
• Confusing rows and columns in the table

4. You created a table calculation in Tableau but the running total is incorrect. You set Compute Using: Table (Across) but the total sums only the first row repeatedly. What is the likely issue?

medium

A. The table calculation is computing across columns but data is arranged in rows, causing repeated sums.

B. You forgot to add the measure to the view.

C. The filter shelf is blocking the calculation.

D. You need to use 'Pane (Down)' instead of 'Table (Across)'.

Solution

1. Step 1: Analyze Compute Using direction vs data layout

   Compute Using 'Table (Across)' moves left to right across columns, but if data is arranged primarily in rows, calculation may repeat first row values.

2. Step 2: Identify mismatch causing repeated sums

   Because calculation moves across columns but data is in rows, it sums the same row repeatedly instead of progressing down rows.

3. Final Answer:

   The table calculation is computing across columns but data is arranged in rows, causing repeated sums. -> Option A

4. Quick Check:

   Compute Using direction must match data layout [OK]

Hint: Match Compute Using direction to data layout orientation [OK]

Common Mistakes:

• Assuming filter shelf causes calculation error
• Thinking measure is missing from view
• Confusing 'Pane (Down)' with 'Table (Across)'

5. You have sales data by Product Category (rows) and Quarter (columns). You want a running total that restarts for each Product Category but sums across quarters left to right. Which Compute Using option should you choose and why?

hard

A. Use Cell because it calculates each cell independently.

B. Use Table (Down) because it calculates top to bottom down rows, restarting per column (Quarter).

C. Use Pane (Across) because it calculates across panes ignoring rows.

D. Use Table (Across) because it calculates left to right across quarters, restarting per row (Product Category).

Solution

1. Step 1: Understand desired calculation behavior

   Running total should sum quarters left to right and restart for each Product Category (row).

2. Step 2: Match Compute Using option to behavior

   'Table (Across)' computes left to right across columns (quarters) and restarts for each row (Product Category), matching the requirement.

3. Final Answer:

   Use Table (Across) because it calculates left to right across quarters, restarting per row (Product Category). -> Option D

4. Quick Check:

   Table (Across) = horizontal running total restarting per row [OK]

Hint: Use Table (Across) for left-to-right running totals per row [OK]

Common Mistakes:

• Choosing Table (Down) which sums vertically, not horizontally
• Confusing Pane and Table options
• Using Cell which does not aggregate across data