Running total in Tableau - Dashboard Guide

Dashboard Mode - Running total

Business Question

How can we track the cumulative sales over months to see the total sales growing over time?

Sample Data

Month	Sales
January	100
February	150
March	200
April	250
May	300
June	350

Dashboard Components

• KPI Card: Total Sales
  Formula: SUM([Sales])
  Result: 1350
• Line Chart: Monthly Sales
  X-axis: Month (January to June)
  Y-axis: Sales
  Shows sales for each month as points connected by a line.
• Line Chart: Running Total of Sales
  X-axis: Month
  Y-axis: Running Total Sales
  Formula (Table Calculation in Tableau): RUNNING_SUM(SUM([Sales]))
  Results:
  January: 100
  February: 250
  March: 450
  April: 700
  May: 1000
  June: 1350

Dashboard Layout

+----------------------+-------------------------+
|      Total Sales      |     Monthly Sales       |
|       (KPI Card)      |       (Line Chart)      |
+----------------------+-------------------------+
|           Running Total of Sales (Line Chart)           |
+---------------------------------------------------------+

Interactivity

A filter for Month allows selecting a range of months. When the filter changes, both line charts and the KPI card update to show sales and running totals only for the selected months.

Self Check

If you add a filter to show only months from March to June, which components update and what is the new total sales?

• All components update.
• New Total Sales = 200 + 250 + 300 + 350 = 1100
• Running Total for March = 200, April = 450, May = 750, June = 1100

Key Result

Dashboard showing monthly sales and their running total with a total sales KPI.

Practice

1. What does the RUNNING_SUM() function do in Tableau?

easy

A. Calculates a cumulative total by adding values step-by-step

B. Finds the average of all values in a column

C. Counts the number of rows in a dataset

D. Filters data based on a condition

Solution

1. Step 1: Understand the purpose of RUNNING_SUM()

   RUNNING_SUM() adds values cumulatively across a sorted dimension, like dates.

2. Step 2: Compare with other functions

   Unlike average or count, RUNNING_SUM() accumulates values step-by-step.

3. Final Answer:

   Calculates a cumulative total by adding values step-by-step -> Option A

4. Quick Check:

   RUNNING_SUM() = cumulative total [OK]

Hint: Think 'running total' means adding values one after another [OK]

Common Mistakes:

• Confusing RUNNING_SUM() with average or count functions
• Thinking it filters data instead of summing cumulatively
• Assuming it resets for each row instead of accumulating

2. Which of the following is the correct syntax to create a running total of Sales in Tableau?

easy

A. RUNNING_SUM(SUM([Sales]))

B. SUM(RUNNING_SUM([Sales]))

C. RUNNING_TOTAL(SUM([Sales]))

D. TOTAL_SUM([Sales])

Solution

1. Step 1: Identify correct function usage

   RUNNING_SUM() wraps an aggregation like SUM() to calculate cumulative totals.

2. Step 2: Check syntax correctness

   RUNNING_SUM(SUM([Sales])) uses RUNNING_SUM(SUM([Sales])) which is valid; others use incorrect or non-existent functions.

3. Final Answer:

   RUNNING_SUM(SUM([Sales])) -> Option A

4. Quick Check:

   RUNNING_SUM(SUM()) is correct syntax [OK]

Hint: RUNNING_SUM wraps an aggregation like SUM inside [OK]

Common Mistakes:

• Using RUNNING_TOTAL instead of RUNNING_SUM
• Placing SUM outside RUNNING_SUM incorrectly
• Using non-existent functions like TOTAL_SUM

3. Given the following daily sales data:

Date | Sales
Jan 1 | 100
Jan 2 | 150
Jan 3 | 200

What is the running total on Jan 3 using RUNNING_SUM(SUM([Sales]))?

medium

A. 200

B. 150

C. 450

D. 100

Solution

1. Step 1: Calculate daily sums

   Sales are 100 on Jan 1, 150 on Jan 2, and 200 on Jan 3.

2. Step 2: Compute running total up to Jan 3

   Running total = 100 + 150 + 200 = 450.

3. Final Answer:

   450 -> Option C

4. Quick Check:

   100+150+200 = 450 [OK]

Hint: Add all previous sales including current date [OK]

Common Mistakes:

• Taking only current day sales instead of cumulative
• Adding only two days instead of three
• Confusing running total with daily sales

4. You created a running total using RUNNING_SUM(SUM([Sales])) but the values reset unexpectedly for each category. What is the likely cause?

medium

A. SUM([Sales]) is incorrect syntax

B. The table calculation is partitioned by category, causing reset

C. RUNNING_SUM() cannot be used with categories

D. Data source has missing sales values

Solution

1. Step 1: Understand table calculation partitioning

   Table calculations like RUNNING_SUM reset when partitioned by a dimension, here category.

2. Step 2: Identify cause of reset

   If partitioning is by category, running total restarts for each category separately.

3. Final Answer:

   The table calculation is partitioned by category, causing reset -> Option B

4. Quick Check:

   Partitioning causes running total reset [OK]

Hint: Check partitioning settings if running total resets [OK]

Common Mistakes:

• Assuming syntax error causes reset
• Believing RUNNING_SUM can't work with categories
• Ignoring partitioning in table calculations

5. You want to show a running total of monthly sales but only for the current year. Which approach correctly applies this filter without breaking the running total calculation?

hard

A. Use RUNNING_SUM(SUM([Sales])) without any filters

B. Apply a regular filter for current year after creating the running total

C. Create a calculated field that sums sales only if year equals current year, then apply RUNNING_SUM

D. Use a context filter for current year before applying RUNNING_SUM(SUM([Sales]))

Solution

1. Step 1: Understand filter order impact

   Regular filters applied after table calculations can break running totals by removing data points.

2. Step 2: Use context filter to limit data first

   Context filters limit data before calculations, preserving running total logic for current year only.

3. Final Answer:

   Use a context filter for current year before applying RUNNING_SUM(SUM([Sales])) -> Option D

4. Quick Check:

   Context filter preserves running total correctness [OK]

Hint: Filter data first with context filter, then run running total [OK]

Common Mistakes:

• Applying regular filter after running total breaks calculation
• Not filtering data, showing all years
• Using calculated field without proper filtering