This method is talking about summing data by month, quarter, or year with a pivot table in Excel. See the detailed steps as follows:

1. Select original data that you will sum by month/quarter/year, and click Insert > PivotTable (or Insert > PivotTable > PivotTable). See screenshot:

2. In the opening Create PivotTable dialog box, specify a place that you will put the created pivot table at, and click the OK button. See screenshot above:

3. Now PivotTable Fields pane is opening on the right of worksheet, drag the Date field (the field you will sum by) to Rows section, and drag the Amount field (the field you will sum) to Values section. See below screenshot:

Note: Apart from dragging, you can also right click the Date field and select Add to Row Labels from the right-clicking menu, and right click the Amount field and select Add to Values from the right-clicking menu. See screenshot above:

4. Now go to the pivot table, right click any date in the Row Labels column, and select Group from the right-clicking menu. See screenshot below:

5. In the opening Grouping dialog box, click to highlight a criteria you will sum by in the By box, and click the OK button. In our case, we click to highlight the Months. See screenshot above:

So far we have created a pivot table and sum the amounts by each month as below screenshot shown:

You may have noticed that the pivot table is not able to sum data by weekday. Do not worry! This method will introduce Kutools for Excel utilities to sum data by weekday, month, or year easily as follows:

1. Select the date cells that you will sum data by, and click Kutools > Format > Apply Date Formatting.

2. In the opening Apply Date Formatting dialog box, click to highlight a date formatting which shows a date as only month, weekday, or year based on your needs, and then click the Ok button. See screenshot above:

In our case, we click to highlight the date formatting of “Wed”.

3. Keep selecting the date cells, and click Kutools > To Actual to convert dates to text of weekday names.

4. Select the data range that you will sum by weekday, month, or year, and click Kutools > Content > Advanced Combine Rows.

5. In the opening Combine Rows Based on Column dialog box, please do as follows:
(1) Select the Date column which you will sum by, and click Primary Key button;
(2) Select the Amount column which you will sum, and click Calculate > Sum.
(3) Set combining rules for other columns, and click the Ok button.

Now you will see the data range has been summed by every weekday, month, or year based on your settings. See below screenshot:

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