In Power Query, you can create a table that contains an aggregate value for each unique value in a column. Power Query groups each unique value, performs an aggregate calculation for each value, and pivots the column into a new table. For example, you could count the number of products in each product category.
To pivot a column
In the Query Editor ribbon, click Transform > Pivot Columns.
In the Pivot Column dialog box, choose a column from Values Column. For example, choose Product Number.
Expand Hide advanced options and choose an Aggregate Value Function. For example, choose Count (All).
Given a products table with a ProductCategory and ProductNumber column, you can get the count of all products in each category.