That’s an interesting list, Marley23. What I find most interesting about it is that it lumps together people who might not wish to be lumped together, such as Roman Catholics and Eastern Orthodox, Sunni and Shiite Muslim, etc.
A re-vamped list looks like this:
Atheism: 1, 782,809,000
Roman Catholic: 981,465,000
Sunni Muslim: 934,850,000
Hindu: 793,075,000
Protestant Christian: 404,020,000
Buddhist: 325,275,000
Other Christian: 282, 258, 000
Orthodox Christian: 218,350,000
Shiite Muslim: 180,212,000
Anglican: 69,136,000
Sikh: 19,508,000
Jews: 13,968,000
Other Muslim: 11,263,000
Baha’i: 6,404,000
Confucians: 5, 086,000
Jains: 4, 620,000
Shinto: 2,897,500