Your increased european sales could be caused by a spike in that traffic.
Did some new webmasters sign up that have nothing but tons of European traffic?
Also my experience with pricing is that "rebillable surfers" don't decline to sign up over a few dollars in price. That's why I never use trials. Not using trials makes more money.
It is the biggest false belief in the world that a surfer will decline a site charging $39.99
because they would rather go to another site that charges $29.99.
There is tons of free porn, so the surfer is only signing up because that particular site
has them hooked. If price were the issue then none of us would ever ever ever get a sign up because there is plenty of porn for free, and free is the best price.
Affiliates have a strange habit of shutting the fuck up when more money than expected appears in their stats.
First, unless the surfer is blind, they will see the price and the option to change it on the sales form; and he can change it to what ever it equaled on the review site.
Second, the surfer is not stupid enought to think that the review site is plugged into all paysites and instantly updates the review when the price has changed.
If you continue to charge in dollars and the going rate for sign ups rises then are you not going to raise your price because someone has a review site and needs to change a page?
No way.
I smell charge back when I join a site in euros/pounds without having a dollar option and then find out that I actually paid $75 dollars for that shit.
Show me the dollars and if I still want it for that price then where is my complaint?