Near as I can tell it has been that price since at least March 2006 http://web.archive.org/web/20060316032049/http://www.allakhazam.com/Premium_Chart.html
We do appriciate each and every premium member though, because you fund the existance of us admins!
Those links probably lead to part of the site that only lets you in if your an admin.
Like where the smiles are located. I remember when I used to be able to access a directory full of alla smiles that didn't all work. Now it's gone forever!