Mailchimp: "Existing Members" Data only for Lists with Campaings?
I'm trying to retrieve Subscribers Data from the past for all my lists. But for some reason, Mailchimp only returns data when the metric "Existing Members" for those lists which had been actively used in the past. "Member Count" only for works for today's current data.
Is there a way to get the past subscriber data even if no campaign was ever sent?