Google has augmented its preferences for personal data retention; in addition to choosing to have all your data stored until you delete it, or having no data stored (thus depriving you of the benefits of personalization), the company has a new intermediate option: a rolling deletion program, which lets you specify that any data older than either 3 or 12 months should be autodeleted. That way, if you suffer a breach (or if authorities demand your data from Google), only your recent activity will be exposed.
Google will now delete your account activity on a rolling basis
