Once a campaign is relaunched, the past instance is ended, and a new one is created in its place. Sometimes you may want to access information from the ended instance. This can be done in the Admin by navigating to the desired campaign, then clicking the arrow next to "Past Campaigns" in the left sidebar. This drops down a list of previous instances of the given campaign, which can be clicked to open their Admin section, where reports on previous data can be accessed.