Thank you for providing your source.
I looked at the reference that statistic led to and lo' and behold, we are citing the same material.
I read the study a bit more carefully this time and there's actually quite a bit of interesting info on the "non-religious" portion if you dive into the details. Specifically, the number of people who answer "atheist" changes slightly depending upon how you ask them. I would wager that a lot of people label themselves as agnostic or non-religious simply because the term carries less baggage, as many believers instinctively associative "atheist" with satanist and are prejudiced to think all sorts of horrible things about us.
http://www.adherents.com/Religions_By_Adherents.html#Nonreligious
While I'm on the topic, I'd like to point out a common misconception between the strict definitions of "atheist" and "agnostic". Most people (including myself until a few years ago) believe that an atheist is one that asserts that there are no gods and an agnostic is one who states that they do not know whether or not there is a god, seen as a "weaker" form of atheism almost. This isn't true, because theism,which deals with belief, and gnosticism, which deals with knowledge, are mutually exclusive terms. You can be both atheist and agnostic, which is in fact what I am. I don't believe there are any gods, but I don't know that there are no gods. I used to refer to myself as an agnostic, despite that I have never believed in any gods at any point in my life, because I viewed the term atheist in the way that is commonly misunderstood. Today, I describe myself as atheist, because it more accurately represents who I am.
So there are four possible combinations when dealing with gnosticism and theism:
- An agnostic atheist is one who does not believe in any gods, but does not claim to know that there are no gods.
- A gnostic atheist is one who does not believe in any gods, and claims to know that there are in fact no gods.
- An agnostic theist is one who believes in a god or gods, but does not claim to know that these gods definitely exist.
- A gnostic theist is one who believes in a god or gods, and claims to know that these gods in fact do exist.
So if someone asks you "Do you believe that there is a god/are gods?" and your answer is anything other than "Yes.", then you are an atheist. Whether or not you choose to use that label to describe your religious views is a personal preference. And this concludes my public service announcement.