'Real' vs 'Nominal'

Am I a 'real' or a 'nominal' Christian?

I recently started a new class at Bible College last Wednesday: Foundation for Mission. Basically, the course is as the name suggests, and on Wednesday we had our introductory lecture. My lecturer started off with a powerpoint slide show outlining a whole lot of statistics, one of which inspired this post.
In the world's population (6 Billion), 33% are Christian (2 Billion). However, out of that overall 33%, 20% are nominal Christians (1.2 Billion). That is, they are Christian 'in name only'. Added to this is the fact that Christianity is the third-fastest growing religion (behind Islam and Hinduism). I am left with the question: why is that? But also I am left with a hair-raiser: What am I?

Let's say for the moment I am a 'real' Christian. I am one who takes the words of Jesus, applies it not only to my own life, but also take opportunities to make a difference in someone else's life, no matter the impact. I hate that which is immoral or wrong, and 'Sin' is something I take seriously.
But let's also flip this proverbial coin. What if I'm a 'nominal' Christian? That would mean that I turn up to Church on Sunday and proceed to 'play the devil' six days a week. I acknowledge that I have sinful areas in my life, but I also acknowledge that I do sin deliberately. If you were asked to distinguish me from the crowd, I would be no different to the Atheist down the road. Jesus is who he said he was, but that makes little impact in my life. I swear, get drunk some weekends, get into trouble on some occasions...and then turn up to Church, thinking everything's going to be alright.

Can you see the picture forming? Out of 2 Billion Christians, 61% of that number are nominal! It's no wonder the stats show Christianity as #3...and it is also falling. And recalling my opening sentence, what am I? Am I part of the problem? Or am I part of the solution?