Allan W. wrote:
We wouldn't necessarily recommend deleting loads of entries, but if that's something that has to happen it'd be good to save a backup as opposed to exporting. That's accomplished through going to the File menu and selecting the Backup menu option. It's completely up to you whether you delete your older entries, ultimately, but it'll be a lot better having a complete backup in hand should you choose to do so.
Also, do keep in mind you that you'll want to update your Account's Starting Balance after the removal of old entries—do that by going to the Account menu and selecting the Edit Account menu option. The new Starting Balance needs to match the value shown in the Balance column for the latest entry being removed, so be sure to note that value before the removal.