I see where your confusion is coming from. When you look at "report by time period" if you are filtering by "day" our datebase only holds subscription data for the past 3 months. In order to keep the load of the reports manageable, this data rolls for 3 months.
That said, if you look at the "report by time period" and filter by "month" you'll see that since you joined you have had those 11 subscriptions and also a handful of rejections. It appears that most of your good subscriptions you did acquire earlier in your partnership with us.
I suggest you contact your account manager, Vince Chiarlone (firstname.lastname@example.org). He can help you manage your offers and promote them in the best ways possible to see better conversions.
For more information about leads, rejects, and conversion rates, check out this blog post:http://www.revresponse.com/promo-tips
Please let me know if you have other questions.