You can access your statistics and campaigns for 90 days on a Free Plan and 13 months on a Paid Plan since their creation. Templates and contacts are retained for the life of the account.
If you are on a Free Plan and wish to access older statistics, you can regularly download your stats or upgrade to a Paid Plan.
When downgrading from a Paid Plan to a Free Plan, the 90-day statistics limitation will be applied after a 60-day grace period. Once this period has expired, all the data older than 90 days will be permanently deleted and cannot be restored even if you subscribe to a paid plan.