3 Replies Latest reply on Oct 10, 2016 6:53 AM by David Li

# Table Calculations

Hi there,

Please see attached image for some dummy data and expected tableau output .. I am planning to calculate % sales using Table calculations.

I am not sure how I am able to calculate the Impr. column using Tableau's table calculations. Any help is greatly appreciated.

Thanks

• ###### 1. Re: Table Calculations

Hi Lavanya, here's what I would do:

1. Create a table calculation for % of total sales. Set it to compute along Pre/Post (so that it only applies within each Category). Let's call this field [% Sales].

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

2. Create a calculated field that gets the Impr. field and add it to the view.

[% Sales] * 2 - 1

3. Hide all but the highest value for Impr. per Category somehow. There are quite a few ways to do this, so let me know if you need more specifics. For instance, you could do a WINDOW_MAX() along [Pre/Post].
• ###### 2. Re: Table Calculations

Thanks for the response, David.

Is there an easy way to write the formula for Impr. field. Its a very simple formula: [Post - Pre].

In the example above, for Cat1, 83.3% - 16.7% = 66.7%

• ###### 3. Re: Table Calculations

The second formula is the Impr. formula.

[% Sales] * 2 - 1

If you look at the table you have above, you see that the expanded formula for Impr. is

%Sales - (1 - %Sales)

This simplifies to

% Sales * 2 - 1

For example:

83.3% - 16.7%

83.3% - (1 - 83.3%)

2 * 83.3% - 1