We're looking to create a user segment for repeat customers. The definition of repeat in this case being users who have made at least 1 purchase before the present month, and made another purchase in this month. For instance, someone who has made a purchase in May and June would qualify as a repeat. However, a user who has made more than 1 transaction in a single month without any purchase in the current month(e.g.., 2 transactions in May, but 0 in June) would not classify as a repeat customer. Is there a way to create a segment on GA?