If you’ve been tracking a lot of detailed data, you may want to analyze it by month so that you can see seasonal trends and smooth out daily variations.
In your spreadsheet, calculate the date of the first day of the month for your data.
- Microsoft Excel: =DATE(YEAR(…), MONTH(…), 1)
- OpenOffice.org Calc: =DATE(YEAR(…); MONTH(…); 1)
where … is a cell reference to the date for that item. (Ex: =DATE(YEAR(B2), MONTH(B2), 1)
Then use a Pivot Table to group your data by that new date.
- Microsoft Excel: Insert > Pivot Table
- OpenOffice.org Calc: Data > Pivot Table > Create
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