You are creating a false dichotomy by limiting the definition of Christian to those that do not accept evolution. The acceptance of Evolution is not restricted to atheists (or at least to non-Christians).
You can't put forward a convincing argument by redefining terms.
If you had read the initial statement, it was making the assumption that they were Christian communities.
You can call yourself "Christian" because you have a family that may have attended a Church once, as many people do, but this does not imply those statistics are Christian.
It was his way of twisting my argument to suit his, and my fault for not making clear to someone who doesn't see the statistic from a Christian perspective.