Percent of total in Tableau - Dashboard Guide

Dashboard Mode - Percent of total

Dashboard Goal

Understand how each product's sales contribute to the total sales in the store.

Sample Data

Product	Sales
Apples	100
Bananas	200
Cherries	300
Dates	400
Elderberries	500

Dashboard Components

• KPI Card: Total Sales
  Formula: SUM([Sales])
  Result: 1500
• Bar Chart: Sales by Product
  Shows sales values for each product from the data table.
• Bar Chart: Percent of Total Sales by Product
  Formula: SUM([Sales]) / TOTAL(SUM([Sales]))
  Result example for Apples: 100 / 1500 = 6.67%
• Table: Sales and Percent of Total
  Columns: Product, Sales, Percent of Total
  Percent of Total formula: SUM([Sales]) / TOTAL(SUM([Sales]))
  Shows each product's sales and its percent contribution to total sales.

Dashboard Layout

+----------------------+-----------------------------+
|      Total Sales      |      Sales by Product        |
|       (KPI Card)      |         (Bar Chart)          |
+----------------------+-----------------------------+
| Percent of Total Sales by Product (Bar Chart)          |
+--------------------------------------------------------+
| Sales and Percent of Total (Table)                      |
+--------------------------------------------------------+
    

Interactivity

Applying a filter on Product updates all components:

• Total Sales: recalculates sum for filtered products.
• Sales by Product Bar Chart: shows bars only for filtered products.
• Percent of Total Sales Bar Chart: recalculates percent based on filtered total.
• Sales and Percent of Total Table: shows filtered rows and recalculates percent.

Self Check

If you add a filter to show only Apples and Bananas, which components update and how?

• Total Sales: updates to 300 (100 + 200).
• Sales by Product Bar Chart: shows bars for Apples and Bananas only.
• Percent of Total Sales Bar Chart: recalculates percentages: Apples 33.33%, Bananas 66.67%.
• Sales and Percent of Total Table: shows only Apples and Bananas with updated percent of total.

Key Result

Dashboard shows sales by product and each product's percent contribution to total sales.

Practice

1. What does the "Percent of total" calculation show in Tableau?

easy

A. Each part's share of the whole

B. The total sum of all measures

C. The difference between two measures

D. The average value of a measure

Solution

1. Step 1: Understand the meaning of percent of total

   Percent of total shows how much each part contributes to the entire total.

2. Step 2: Relate to Tableau usage

   In Tableau, this is used to see the share of each category or item compared to the whole dataset.

3. Final Answer:

   Each part's share of the whole -> Option A

4. Quick Check:

   Percent of total = part / whole [OK]

Hint: Percent of total means part divided by whole [OK]

Common Mistakes:

• Confusing percent of total with sum
• Thinking it shows difference instead of share
• Mixing average with percent of total

2. Which of the following is the correct Tableau formula to calculate percent of total for a measure named Sales?

easy

A. SUM([Sales]) / TOTAL(SUM([Sales]))

B. TOTAL(SUM([Sales])) / SUM([Sales])

C. SUM([Sales]) * TOTAL(SUM([Sales]))

D. SUM([Sales]) - TOTAL(SUM([Sales]))

Solution

1. Step 1: Identify the correct formula structure

   The percent of total is calculated by dividing the sum of the part by the total sum.

2. Step 2: Match with Tableau syntax

   In Tableau, TOTAL() wraps the aggregation to get the grand total, so SUM([Sales]) / TOTAL(SUM([Sales])) is correct.

3. Final Answer:

   SUM([Sales]) / TOTAL(SUM([Sales])) -> Option A

4. Quick Check:

   Part / Total = SUM / TOTAL(SUM) [OK]

Hint: Divide SUM by TOTAL(SUM) for percent of total [OK]

Common Mistakes:

• Reversing numerator and denominator
• Using multiplication instead of division
• Subtracting instead of dividing

3. Given a dataset with categories A=100, B=300, and C=600 sales, what is the percent of total for category B using SUM([Sales]) / TOTAL(SUM([Sales]))?

medium

A. 10%

B. 30%

C. 60%

D. 50%

Solution

1. Step 1: Calculate total sales

   Total sales = 100 + 300 + 600 = 1000.

2. Step 2: Calculate percent of total for category B

   Percent = 300 / 1000 = 0.3 or 30%.

3. Final Answer:

   30% -> Option B

4. Quick Check:

   300 / 1000 = 0.3 = 30% [OK]

Hint: Divide category value by total sum, then convert to percent [OK]

Common Mistakes:

• Adding instead of dividing
• Using wrong total value
• Confusing category values

4. You wrote the formula SUM([Sales]) / TOTAL(SUM(Sales)) but Tableau shows an error. What is the problem?

medium

A. Using SUM instead of AVG

B. Division operator is incorrect

C. TOTAL function cannot be used with SUM

D. Missing square brackets around Sales in TOTAL function

Solution

1. Step 1: Check syntax of field references

   In Tableau, field names must be enclosed in square brackets inside functions.

2. Step 2: Identify missing brackets in TOTAL function

   The formula uses TOTAL(SUM(Sales)) but should be TOTAL(SUM([Sales])).

3. Final Answer:

   Missing square brackets around Sales in TOTAL function -> Option D

4. Quick Check:

   Field names need [ ] in functions [OK]

Hint: Always use [ ] around field names inside functions [OK]

Common Mistakes:

• Omitting brackets around field names
• Using wrong aggregation functions
• Incorrect operator usage

5. You want to show the percent of total sales by region in a bar chart. Which steps correctly apply this in Tableau?

hard

A. Create a calculated field: TOTAL(SUM([Sales])) / SUM([Sales]), then use Region on Rows

B. Use SUM([Sales]) only, then sort bars descending

C. Create a calculated field: SUM([Sales]) / TOTAL(SUM([Sales])), format as percentage, then use Region on Columns and this field on Rows

D. Create a calculated field: SUM([Sales]) - TOTAL(SUM([Sales])), then use Region on Columns

Solution

1. Step 1: Write correct percent of total formula

   Use SUM([Sales]) / TOTAL(SUM([Sales])) to get each region's share.

2. Step 2: Build the visualization

   Place Region on Columns and the calculated percent field on Rows, then format as percentage for clarity.

3. Final Answer:

   Create a calculated field: SUM([Sales]) / TOTAL(SUM([Sales])), format as percentage, then use Region on Columns and this field on Rows -> Option C

4. Quick Check:

   Percent of total formula + proper chart setup [OK]

Hint: Divide SUM by TOTAL(SUM), format %, use region on axis [OK]

Common Mistakes:

• Using subtraction instead of division
• Reversing numerator and denominator
• Not formatting as percentage