Aggregate calculations
We’ve already considered aggregations such as sum, min, and max in Tableau. Often, you’ll use fields as simple aggregations in the view. But sometimes, you’ll want to use aggregations in more complex calculations.
For example, you might be curious to explore the percentage of the rent that was discounted. There is no such field in the data. It could not really be stored in the source, because the value changes based on the level of detail present in the view (for example, the discount percentage for an individual unit will be different from the discount percentage per floor or per building). Rather, it must be calculated as an aggregate and recalculated as the level of detail changes.
Let’s create a calculation named Discount % with the following code:
SUM([Discount]) / SUM([Rent])
This code indicates that the sum of Discount should be divided by the sum of Rent. This means that all the values of Discount will be...