Tableau Table Calculations are a special type of calculated field. Unlike regular calculated fields, these are based on the data that is currently visualized in a report. This article shows how to create Tableau table calculations, and how to use their properties.
For these Tableau Table calculations demo, we use the Global Super Store Excel Worksheet. Before creating them, let me create a simple report.

Create Tableau Table Calculations
In Tableau, you can create table calculation in multiple ways, and the first approach is: Right-click on the measure, and select Create -> calculated Fields. The second approach, please navigate to Analysis Tab and select Create Calculated Field… option
Please refer to Tab Report, calculated field and Connecting to the Excel Files in Tableau.

Selecting the Create Calculated Field… option will open the following window. Here, we renamed the default name as Cal. The below statement will find the First records in this data. Here, you can click OK to close this window

Or you can click Default hyperlink (marked below) to alter the default settings, and it opens the following window.

Use this window to change the Calculated field, Levels, etc. I am not a fan of making any modifications using this window. However, you can do it. Let me click Cancel button to close the window, and then click OK button

Let me drag this first Cal to the Measures shelf in the Tableau design area.

Edit Tableau Table Calculations
Click the down arrow, and select the Compute using to change the computing options.

Let us see the list of available options. For this, let me select the Edit Table Calculation option.

It will open a new window called Edit calculation.
Table Down Calculation
Tableau Table Down Calculations will start calculating from the first row to the end row in a complete table.

Pane Down
The Tableau Pane Down Table Calculations will calculate from the first row to the end row in a Pane or group. From the below screenshot, the First is applying for each quarter.

Specific Dimensions
You can use any dimensional column to compute the Tableau Table calculation. Here, it is applying the FIRST function for each year.

You can also change the Sort order, and sorting column

Let me add Segments filed to Columns shelf to explore a few more options. As you can see, it is displaying a few more options.

Table across
Tableau Table Cross Calculations will apply the first function for each row in a table.

Table across then down
The Tableau Table across then down Calculations will apply the first function for each row in a table and then go to the next row.

Table down then across
It will apply the first function for each row in a column and then go to the next column.

Pane Down
It will calculate from the first row to the end row in a Pane or group.

Pane Down then down
It will calculate from the first row to the end row in a Pane or group.

Tableau Table Calculation Specific Dimension
As we said before, use your own dimension to compute the calculation. Here, it is applying the FIRST function for each quarter.

The FIRST function calculates for each quarter and segment.

Here, the FIRST function applies for each year and segment.
