Using the Power Query Add-In - Microsoft Business Intelligence Tools for Excel Analysts - page 130

Figure 7-5: Power Query adds your custom column specifying that each row counts as one station.
Figure 7-6: Group by the Format column and sum the Custom column into an aggregate column called
Count of Stations.
5. Select Format from the Group By drop-down menu, enter Count of Stations in the New
Column Name box, select Sum from the Operation drop-down menu, and select Custom
from the Column drop-down menu. Click OK when you're done.
Power Query then groups by the Format column and sums the Custom column into an
aggregate column called Count of Stations.
Now there is one row for each radio station format. Each row shows the count of radio stations.
6. Click the Sort command on the Query Editor Ribbon to sort by the Count of Stations column.
You get the results shown in Figure 7-7.
Now you know how many radio stations Maryland has dedicated to sports: 9.