Once you launch a survey with aytm your survey and the results associated with it will remain in your Dashboard under the Completed section. You will have access to view your data as long as you keep the survey in your dashboard. 

Deleting a Survey

If at any time you decide to delete a survey from the Dashboard, survey data will also be deleted. Still want to continue? Follow these steps. Toggle to the Completed or Drafts section of your Dashboard. Surveys can be deleted from each of these sections. Select the gear icon to the right of the study title. Click Delete. Click Delete Forever.

If you are looking to permanently delete your account and all your survey data check out this article here.