The Intervals tab of the Data Set update page is used to select the intervals from which to export data.

A list of fixed and non-fixed intervals in the project are displayed.

Mark the checkbox next to each interval from which to export data
To include all fixed intervals in the data set, mark the checkbox next to "All Fixed Intervals" or select each interval individually

No intervals need to be marked if the data set will only include universal and/or project variables

If any non-fixed intervals are marked, the data set export can not be collapsed

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