Working with Report Manager - Learning SQL Server Reporting Services 2012 - page 224

4. Provide a Description and accept the default Specify for this subscription

only . Choose E-Mail from the drop-down list for Specify how recipients are
notified and click on the Next button.
The other options in the drop-down list are Windows File Share and Null
Delivery . Null Delivery will not deliver but if Report Cache is enabled then
the result of executing the subscription with this setting will end up here.
This may be useful in cases where you may want to keep copies of a report
that depend on various parameter settings.

5. Fill it out as shown in the following screenshot:

6. Click on Next .