This afternoon I was walking between buildings on campus and I saw a sign up for a "talk". The headline reading "There Are No Happy Atheists".
That got me thinking. Am I happy? I realized that in general I'm not really happy. I have the capacity for happiness. From time to time I am afflicted with a case of happy. But happy is not my baseline state. Hell, I wouldn't want to be happy ALL the time. Sounds like way too much work.
If I had to pick an emotional state as my baseline, it would have to be content. Some times I'm more content than other times. If I'm reading a good book before bed, I'm content. If I'm scrambling to finish a homework assignment at two in the morning, I'm less content. And all the times that I have been happy or sad, sky-poppa had absolutely nothing to do with it.
Happy, Sad, these are emotions that I suspect are not designed to be experienced perpetually. I'd say that anyone who does is likely the victim of some mental disease.
To answer the question, at any particular moment there are at least a high a percentage of happy atheists in the atheist demographic as there are happy theists in their demographic.
As always, I don't care what superstition you want to entertain. All I ask is for you to leave me out of it.