Bar charts (horizontal and vertical) in Tableau - Cell-by-Cell Formula Trace

Concept Flow

Category    Sales
Books      150
Clothing   200
Electronics 300
Furniture  100

Step 1: Group by Category
Step 2: Sum Sales per Category
Step 3: Plot bars with Category and Sales

We start with sales data by category. We group the data by category, sum the sales for each group, then plot bars where each bar length shows total sales for that category.

Formula

SUM([Sales]) by [Category]

This Tableau formula groups sales data by category and sums the sales values for each category to prepare data for bar chart plotting.

Step-by-Step Trace

Category	Sales
Books	150
Clothing	200
Electronics	300
Furniture	100

The table shows total sales per category after grouping and summing.

Variable Tracker

Variable	Value	Explanation
Category Groups	Books, Clothing, Electronics, Furniture	Categories identified for grouping
Sales Sum per Category	150, 200, 300, 100	Sum of sales values for each category
Bar Lengths	150, 200, 300, 100	Bar lengths correspond to summed sales

Key Moments

What does grouping by Category achieve?

How is the sales sum calculated?

What does the bar length represent in the chart?

Sheet Trace Quiz - 3 Questions

Which step shows the total sales for Electronics?

A Step 1: Group data by Category

B Step 3: Plot bars with Category on axis

C Step 2: Calculate sum of Sales for each Category

D None of the above

Key Result

Bar charts visualize grouped and summed data by showing bars whose lengths represent values like sales totals per category.

Transcript

We start with sales data by category. First, we group the data by category names. Then, we sum the sales values within each group. Finally, we plot bars where each bar's length shows the total sales for that category. This can be done vertically or horizontally in Tableau by placing Category on one axis and the summed Sales on the other. The longer the bar, the higher the sales amount. This simple visual helps compare categories easily.