What percent of the world follows Christianity?

As of mid-2007, about 33% of people world-wide are considered Christians. Source: http://Christianity.about.com/gi/dynamic/offsite.htm?zi=1/XJ&sdn=christianity&cdn=religion&tm=85&gps=150_340_1005_615&f=00&tt=11&bt=0&bts=0&zu=http%3A//www.gordonconwell.edu/ockenga/globalchristianity/resources.php