However, I also realize that this number is completely incomparable to the amounts of games that better-known full-time designers sell every year. A game that wins the Spiel des Jahres, the Game of the Year award in Germany, for example, typically sells at least ten times this number!
Of course, a full-time designer works under the pressure of having to sell lots of games each year. Game designers' royalties are too meager to rely on average sales from single titles to support them. To put this into perspective, even if I would have sold four times the number of games since 2008, my income would still put me below the poverty level in the United States. It's a good thing I'm not trying to support my family with my game design hobby, and I wouldn't recommend anyone else trying to do this, either, unless he or she is already milking an established hit.
In an interview I once read, designer Alan Moon said that it took a second Spiel des Jahres win for his Ticket to Ride game--and numerous spin-off games--to keep him from having to look for a second job. And this was in the middle of the most productive time in his career, when he was releasing a large number of new games with different publishers every year.
My goal has never been to make game design my career, and I'm quite content to focus on a few designs in my free time and have at least one new game published each year. That does not mean, of course, that I don't take my designs seriously. And I certainly want to maintain a level of professionalism in my interactions with the industry. But it is ultimately the feedback from fans and good times with friends and family around the gaming table that are the best royalty checks.