★ 'Pentecostalism' - 105 million (Royal Geographic Society figures). Estimates vary widely. The World Christian Encyclopedia, published in 1982, estimated that the worldwide total of Pentecostals was "close to one hundred million." The Penguin Concise Encyclopedia estimates "over 22 million" Pentecostals, as does the Cambridge Encylcopedia, while the Oxford Dictionary of World Religion estimates "at least 130 million". The number of members claimed by different Pentecostal groups are: