There is a limitation on how far back data can be retrieved in Analytics. Depending on your organization’s subscription configuration that applies to the relevant site, it can be limited to a storage duration of 13, 26, or 61 months.

This means that:

• New one-off reports contain only data from within the storage duration
  (note: recurring reports cannot be created with a start date that is in the past)
• Existing reports / report editions are preserved

Note that data points must first be added to the Historical Data Storage to become available to be included in reports (more info). Data from before the data point was added to the Historical Data Storage cannot be retrieved. As a result, data may not or only partially be shown in your report.

New one-off reports contain only data from within the storage duration

You cannot create a report with an end date prior to the storage duration.

Reports may contain partial data: if you create a report with a start date prior to the storage duration, the data before the storage duration will not be shown in the report. Charts and scatter plots will automatically adjust to show only the data for the period in which data is available.

Existing reports / report editions are preserved

Don’t worry, you won’t lose any existing reports without a warning. A published report that contains data older than the storage duration will be preserved. A report is basically a captured snapshot; as long as a report is not regenerated, it will be kept forever. This applies to both one-off and recurring reports.

Regenerating reports
After editing the template, you’ll need to regenerate the report. It’s made impossible to regenerate a report whose end date is longer ago than the storage duration. This prevents you from losing data in your report.

However, it is possible to regenerate a report that is partially within the storage duration. You will get a warning that some of the data will be lost if you proceed.

This also applies to recurring reports. After editing the template of a recurring report, the report editions can be regenerated one by one. In the example below it is not possible to regenerate edition 1 and when regenerating edition 2 you will get a warning that some of the data will be lost if you proceed.