Here's how to group and aggregate data using Power Query (SUM, AVERAGE, COUNT):

1. Group By:

* Select the columns you want to group your data by.
* Go to the Home tab in Power Query Editor.
* Click on Group By.

Advanced Grouping (Optional):

* If you want to group by multiple columns, select Advanced in the Group By dialog box.
* Click Add grouping for each additional column you want to include in the grouping.

2. Add Aggregations:

* In the Group By dialog box, under New column name, enter a name for your aggregated column (e.g., Total Sales).
* From the Operation dropdown, select the aggregation function you want to use (SUM, AVERAGE, COUNT, etc.).
* In the Column dropdown, select the column you want to aggregate (e.g., Sales).

3. Expand or Collapse Groups (Optional):

* You can expand or collapse groups to see the underlying data by clicking the plus or minus signs next to the group headers in the results.

4. Additional Options:

* You can also keep all rows expanded (Show all rows) or only the top or bottom N rows within each group.
* Power Query offers other aggregation functions like MIN, MAX, VAR.P, etc.

Here's an example:

Suppose you have a dataset with columns for Product, Color, and Quantity. You want to find the total quantity sold for each product.

1. Group By: Select the Product column.
2. Add Aggregation: Name the new column "Total Quantity", select SUM from Operation and choose Quantity from Column.

This will create a new table summarizing the total quantity sold for each unique product.