You will certainly want to create groups of seven days that begin with the first day of the week.
To do so, you must locate the first Sunday or Monday of the data table and define it as a date to begin grouping the dates.
Often, the location of the first Sunday will be before the first date of the data table. For example (see screen shot), the first date of the data table is 5/10/1996. To determine if this is a Sunday:
The result – Friday. The conclusion – the first Sunday before 5/10/96 is 5/5/96.
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