Disclaimer: I am not a statistician, I am merely interested. If you have any better numbers, let me know.
Students Enrolled (2007):
18 200 000
World Population:
1995: 5 713 073 000
2000: 6 115 367 000
Average(2007): 5 914 220 000
Percent of World Population Enrolled in College:
18 200 000 / 5 914 220 000 = 0.0030773288
or 0.308%
Sources:
http://howtoedu.org/college-facts/how-many-people-go-to-college-every-year/
http://esa.un.org/unpp/
