If your business operates on a fiscal year other than January to December or if your reporting week starts on a specific day, you can change the default settings for your account so you don't have to edit it with each metric or dataset (usually through SQL).
Note: Only account admins and users with "Manage Company Info" permissions can edit this.
Go to Settings > Company Info > Then scroll to the bottom where you will see "Date Settings"
Here you can select the start date for your fiscal year. This will be used when filtering the data by any fiscal date range.
You can also select the default day that you use to start your reporting week. This is used when grouping or filtering the data, and you can override the default at any time.