In a discussion over at LinkedIn's Circulation Network Group, a networking group of mainly print publication circulation marketers, the question came up, “What are your conversion rates for trial issues marketed online?”Print newspapers, newsletters and magazines all now fairly routinely offer a trial print subscription online. However, most don't require a credit card number for a trial — instead they rely on heavy follow-up marketing to close the deal and “convert” the trial to a paid subscriber.The circulation execs in question cited ranges between 13-35% for this type of conversion, often dependent on how much marketing follow-up they invested in. Most said they used a combination of telemarketing and direct postal mail to get the conversion.Worth noting, very, very few subscription sites (aside from high ticket b2b content) use any offline marketing to encourage conversions from trials to regular subscribers. Most just depend on email and hope for return site visits. Perhaps they should be a bit more proactive?