Number of Active Developers

Hi all,

I am curious to know the number of community developers contributing code to the Asterisk project. Part of any open source project’s strength lies in the community behind it. I am writing a paper to convince people of the power of Asterisk due to many factors including its community.
The number of the community members is clear, but how many of those are contributing code? How many of them get their code accepted? I know these might be hard numbers to get, but just in case, let me please know.
I know as well that a community has advantages other than contributing code; some members stress test the product, others report bugs and some contribute in the learning process, etc…