Summary of Issues Received

Within the Serials function, when you are creating a New Subscription you generally leave the box for Manual history unticked.  Koha will then build a list of issues received automatically as you are receiving the issues and keep the Summary updated.  The Summary of issues received is displayed on the Subscriptions tab in the staff interface: 

And under More details on the OPAC:

If you want to add in details of other issues which are outside the prediction pattern (back issues for example) or if you want to delete details of issues which you no longer hold, just Edit Subscription and tick the Manual history box and Save:

Now when you go to the Planning tab there is an option to Edit history:

When you have saved your changes be sure to go back and Edit Subscription again to untick the Manual history box, otherwise Koha will not update the Summary when you receive future issues as the system will expect you to enter the details manually.