Years ago I renewed my C&D subscription for 6 years, then a month or two later, a student came to the house selling magazine subscriptions - I got a 10 year renewal on that one! I don't remember the cost back then, but both were a good deal. Those renewals ran out about a year ago. Now I just go year to year, but I'm going to check this out.
I've subscribed to C&D for about 23 years now.