Credit sales are getting more and more rare, and now, essentially, they're a subs site.
When you say 90% of your sales are from the partner program, are you literally meaning from Thinkstock, rather than subs or G+?
Although falling credit sales is commonly reported, over the past few months, I've read people saying their PP sales are falling, though subs are increasing, to a limited extent. (I'm not in the PP.)