In the mid-1960s, Anglican researcher David B. Barrett wrote an article on African Independent Churches for the World Christian Handbook (WCH),[1] a publication that reported only on a portion of the Anglican and Protestant worlds. After contributing to the WCH, Barrett was determined to extend this kind of analysis to all Christian bodies and consequently produced the World Christian Encyclopedia[2] (WCE-1) that documented, for 1980, the existence of over 20,000 Christian denominations worldwide. Barrett developed a seven-fold division among churches: Anglicans, Catholics (non-Roman),[3] non-white indigenous, marginal Christians, Protestants, Orthodox, and Roman Catholics. Each of these major traditions was subdivided into minor traditions — or example, Protestants as Lutherans, Baptists, Presbyterians, and so on.[4]
Pentecostals and Charismatics appeared in these listings in three ways. First, among Protestants were the Classical Pentecostal denominations.[5] However, to illustrate the significant differences between them, sub-categories of Oneness, Baptistic, Holiness, Perfectionist, and Apostolic were developed. Second, Pentecostals outside of the Western world who had split off from established Protestant denominations were labeled as non-white indigenous with sub-category codes similar to those used for Protestant Pentecostals. Third, Barrett recognized the existence of Charismatic individuals within other traditions — designated “neo-Pentecostals”[6] and evaluated by country as “pentecostals” (with a small “p”),[7] illustrating renewal within an existing tradition.
It is important to note that the history of counting Pentecostals is directly related to that of counting Christians as a whole; that is, first, Christians are counted, and then certain Christians are identified as Pentecostals. This is the reason that virtually all estimates for the number of Pentecostals in the world are related to Barrett’s initial detailed work. Barrett was, in fact, the only academic who produced estimates for global Pentecostalism based on individual denominational figures for every country in the world.[8]
In 1988, Barrett published a significant article in which he developed the Three Wave taxonomy.[9] This typology describes the 20th-century “Pentecostal-Charismatic Renewal” as unfolding in three chronological waves.[10] The First Wave included denominational “Classical” Pentecostals founded from 1900 on; the Second Wave, Charismatics in the mainline denominations in movements that started in and after 1960; and the Third Wave, independent Charismatic networks around the world, many emerging after 1980. The vast majority of independent Charismatics were placed in the First Wave (64 out of 75 million in 1970, 104 out of 169 million in 1980), as were all of the break-off groups from Protestant Pentecostalism. The Third Wave, at that time still in its infancy as a concept, was relatively small in size (see table 8 below).
In the second edition of the World Christian Encyclopedia (WCE-2), the non-white indigenous category was changed to “Independents,” and Catholics (non-Roman) were moved to “Independents,” resulting in six major traditions instead of seven.[11] In the assessment of the Pentecostal situation, independent schisms from Classical Pentecostalism were moved to the Third Wave, which was now labeled as Independent Charismatic or Neo-charismatic. This new taxonomy caused a major shift in the numerical sizes of the three waves; the First Wave, the largest category in the earlier surveys, was now much smaller (see table 8). The three waves were collectively called “Spirit-empowered Christians.”[12]
| WCE- 1 | 1988 survey | WCE- 2 | WCE- 1 | 1988 survey | |
| 1970 | 1970 | 1970 | 1980 | 1980 | |
| Pre-Pentecostals [13] | – | 3,824,000 | 3,824,000 | – | 4,438,000 |
| Pentecostals | 36,794,000 | 64,335,000 | 15,382,330 | 51,167,000 | 104,546,000 |
| Charismatics | 1,588,000 | 3,789,000 | 3,349,400 | 11,004,000 | 45,545,000 |
| Neo-charismatics | – | 50,000 | 53,490,560 | – | 4,000,000 |
| Total Spirit-empowered Christians | 38,382,000 | 71,998,000 | 76,046,290 | 62,171,000 | 158,529,000 |
| Unaffiliated pentecostals | – | 3,362,000 | 5,300,000 | – | 10,700,000 |
| Total professing | – | 75,360,000 | 81,346,290 | 100,000,000 | 169,229,000 |
| WCE- 1 | 1988 survey | WCE- 2 | |||
| 2000 | 2000 | 2000 | |||
| Pre-Pentecostals | – | 7,300,000 | 7,300,000 | ||
| Pentecostals | – | 268,150,000 | 65,832,970 | ||
| Charismatics | 38,800,000 | 222,077,000 | 175,856,690 | ||
| Neocharismatics | – | 65,000,000 | 295,405,240 | ||
| Total Spirit-empowered Christians | – | 562,527,000 | 544,394,900 | ||
| Unaffiliated Pentecostals | – | 56,800,000 | 78,327,510 | ||
| Total professing | – | 619,327,000 | 622,722,410 |
After the 1988 survey, Barrett published figures for Spirit-empowered Christians in many places. At the time he was finishing the WCE-2, he also updated the 1988 survey in the second edition of the Dictionary of Pentecostal and Charismatic Movements.[14] These continue to be the most widely-quoted figures of Spirit-empowered Christians (usually ranging from 500 to 600 million for 2000–2010).[15]
Barrett’s efforts to count Pentecostals have been critiqued in three ways: (1) general statements about inflated numbers or not trusting statistics; (2) the chronological inconsistencies of the three-wave typology; and (3) which groups should be defined as Pentecostal or Charismatic.
The first critique — that his estimates were inflated or that statistics cannot be trusted — was the most prevalent and the least helpful. These comments were almost always general statements that were not accompanied by any substantial evidence. Examples of unsubstantiated critiques include calling his estimates “wild guesses,” “uncertain and contested,” “debatable,” and “inaccurate and inflated.”[16] At the same time, leading scholars presented estimates with no documentation whatsoever, such as when David Martin reported that there were 250 million Pentecostals in the world, he appeared to have no direct reference for the number, citing only “a conservative source.”[17]
Second, the three-wave typology suffered from inconsistencies in its chronological sequence. For example, the third wave (Independent Charismatics) predated the first two (Pentecostals, Charismatics) by 150 years. In addition, the three-wave typology was used by some Pentecostals to promote the renewal movement as God’s initiative in the 20th century. For these and other reasons, “wave” terminology was abandoned for the current analysis and replaced with three “types.”
From a demographic point of view, the third critique is the most important and helpful. Barrett’s global figure is a composite of thousands of individual figures (denominations and networks) covering every country of the world. Because the global figure is a composite figure, the only way to critique it is to dismantle the taxonomy by identifying which groups do not belong or which groups have been left out. Despite all the critiques, such an analysis of the taxonomy has never been done. Anderson critiques the general number as too high — “considerably inflated by including such large movements as African and Chinese Independent churches and Catholic Charismatics” — and then goes on to rebuild a taxonomy of four types that appears to include all of Barrett’s groups.[18]
In 2006, the Pew Research Center published a report titled “Spirit and Power: A 10-Country Survey of Pentecostals”[19] with findings from 10 countries.[20] The report referred to Barrett’s earlier work, even utilizing “Spirit-empowered Christians” for the overarching term. While the survey did not produce a new global total (citing instead Barrett’s global figure), it performed the first extensive professional survey of Pentecostalism outside the Western world. The report revealed that Barrett’s “inflated” figures were too low in some key countries. For example, the World Christian Encyclopedia (2001) reported that 47% of Brazilians identified with renewal, while Pew’s survey in 2006 reported 49%. In Guatemala, WCE reported 22%[21] and Pew reported 60%.[22]
In 2010, in partnership with the Pew Research Center, the Center for the Study of Global Christianity (CSGC) embarked on a new assessment of Pentecostalism in every country of the world. While this project borrowed much from earlier attempts, a number of changes were made. First, the term “wave” was abandoned for the less prescriptive term “type.” The three types are roughly approximate to the earlier “waves.” Second, the methodology for calculating the number of Pentecostals was made more explicit. Third, the estimates were sourced for each denomination and for each percentage. The results of this survey were published in Pew’s Global Christianity report.[23]
For this new project, the central research question remained, “How many Pentecostals are in each country of the world, and how fast are they growing?” This question could not be answered by government censuses or social scientific surveys because they are limited in scope (only half of the countries of the world ask a question on religion)[24] and in depth (most censuses and surveys do not ask about Pentecostals), or change over time (more than one date has not been surveyed). Consequently, the only comprehensive method for counting Pentecostals builds on demographic data on Christian denominations.
David Barrett began to collect documents related to the demographics of Christian denominations beginning around 1960. These documents accumulated and were archived, first in Kenya, and later in Richmond, Virginia. By the time the Center for the Study of Global Christianity was established at Gordon-Conwell Theological Seminary in 2003, the team had amassed over 8,000 books and one million documents, including everything from unpublished manuscripts to articles in obscure journals from Africa, Asia, and Latin America. Since 2003, approximately 2,000 books and 100,000 additional documents have been added to the collection.
As this collection of documentation has grown, counting Pentecostals and Charismatics has become more firmly based on membership statistics of denominations in each country of the world, of which the CSGC has now identified approximately 45,000, and each of these denominations belongs to one of four Christian traditions: Independents, Orthodox, Protestants (including Anglicans), or Catholics. These four are detailed to a second level of approximately 300 minor Christian traditions. Some examples include Anglican Evangelicals, Independent Baptists, Latter-day Saints, Russian Orthodox, Presbyterians, and Byzantine Catholics. This system provides the basis for analysis of subsets of Christianity, such as Pentecostals.
A demographic overview of Pentecostalism (all types) illustrates the complexities of both the spread of the movement across the countries of the world and the striking diversity of the churches themselves. While current ways of understanding Pentecostals, Charismatics, and Independent Charismatics reveal a global movement of immense proportions, perspectives on classification, counting, and assessment of the movement are likely to continue to evolve in the future. In the meantime, hundreds of millions of Christians across all traditions will continue to participate in the movement — bringing vitality in some denominations and schism in others. They will also promote social transformation in some communities and show little participation in others. What is certain is that, for the foreseeable future, Christianity as a whole will continue to experience the growth pains of this global phenomenon.
