Why LOD expressions control aggregation scope in Tableau - Formula Trace Breakdown

Sample Data

Sales data by Region and Category

Cell	Value
A1	Region
B1	Category
C1	Sales
A2	East
B2	Furniture
C2	100
A3	East
B3	Technology
C3	200
A4	West
B4	Furniture
C4	150
A5	West
B5	Technology
C5	300

Formula Trace

{FIXED [Region] : SUM([Sales])}

Step 1: SUM([Sales]) for Region = 'East'

Step 2: SUM([Sales]) for Region = 'West'

Step 3: {FIXED [Region] : SUM([Sales])} returns sales sum per Region

Cell Reference Map

    A       B          C
1 |Region | Category | Sales
2 | East  | Furniture| 100  
3 | East  | Technology| 200 
4 | West  | Furniture| 150  
5 | West  | Technology| 300 

The formula uses Sales values grouped by Region ignoring Category

Result

    A       D
1 |Region | Fixed Sales
2 | East  | 300
3 | West  | 450

The LOD expression shows total sales per Region ignoring Category detail

Sheet Trace Quiz - 3 Questions

What does the LOD expression {FIXED [Region] : SUM([Sales])} calculate?

A Total sales for all data ignoring Region and Category

B Total sales per Region ignoring Category

C Total sales per Category ignoring Region

D Sales for each individual row

Key Result

LOD expressions fix aggregation scope to specified dimensions ignoring others