This book is virtually unique in that Operation World 2010 (OW) is one of the very few global statistical surveys of Christianity available. The World Christian Database (online) and the "World Christian Encyclopedia" edited by David Barrett and Todd Johnson(Oxford Universtity Press, 2001)would be the only other two sources for world Christianity. The statistics for Evangelicals in the "World Christian Encyclopedia" are considerably lower than those found in OW, though the statistics found in the World Christian Database are much more closely aligned given the cooperation between these two groups and the agreement in terminology. The method for acquiring the statistics in OW was done in the most scrupulous and thorough manner possible, though sometimes the compilers have had to resort to mathematical extrapolation.
Operation World 2010 (OW) presents every nation of the world beginning in alphabetical order and then offers statistics regarding its geography, population, population growth, ethnicities, languages spoken, economics, political status, and finally religion. Religion is broken down further into the major religions such as Christian, Muslim, Buddhist, Hindu, Jewish, etc. and then a more detailed breakdown of the Christian denominations of each country. And so if you were curious about the number of Christians in the up and coming economic superpower, BRIC, you'd find: Brazil is 72 % Roman Catholic and 26 % Evangelical. Russia is over 50 % Russian Orthodox and 1.2 % Evangelical. India is 74 % Hindu, 14 % Muslim, and 2 % Evangelical. China is 44 % Non-religious and 5 % Evangelical. The top 20 denominations of each country are then listed showing the number of congregations, number of members and number of members and the total number affiliated with each denomination. And so the second largest denomination in the UK, The Church of England, has 16,100 congregations, 1.2 million members and a total of 21.9 million affiliates. Since Operation World is Evangelical in focus it then gives the percentage of the population that is Evangelical, the actual number of Evangelicals, and the annual growth rate. OW then offers the same statistics for Charismatics and Pentecostals, though the number of Pentecostals is also included in the number of Charismatics. This subsequent breakdown of Charismatics and Pentecostals can be confusing because Pentecostals are simultaneously counted as a subset of Evangelicals as well. Charismatics, to complicate the overlap even further, are SOMETIMES considered Evangelicals and SOMETIMES not considered Evangelicals. So there is a significant degree of overlap in the statistics for these three key groups and the vast majority of readers of OW are either Evangelical, Charismatic or Pentecostal. And so for the UK Evangelicals make up 8.8 % of the population, though only a third of this number attend church regularly, with over 5.4 million people. Charismatics make up 4.7 % of the UK with over 2.9 million while Pentecostals make up 1 % of the population with 635,000. Finally the number of missionaries from each country is shown and so we find the UK's Protestants, Independents and Church of England send out 6,405 long term missionaries and 5,726 international missionaries. OW 2010 then outlines Answers to Prayer and Challenges for Prayer for each country ranging from a single page for Iceland to ten pages for the USA. I myself am acquainted with a number of countries on the continent and can verify that the statistics regarding the number of Evangelicals along with the overall assesment of the situation in those countries is relatively accurate, though not without biases. Also, OW concedes that labeling someone Evangelical can be quite challenging at times given that certain denominations are thoroughly Evangelical whereas other institutions such as the State churches of Germany and Scandinavia and Britain contain an Evangelical population that is difficult to count. Also, certain types of Roman Catholics and Eastern Orthodox might be considered Evangelical if they meet the following criteria: 1) Christians who believe in Christ as the sole source of their salvation through faith in Him. 2) Christians who evince a personal faith in Christ stemming from a conversion exerience. 3) Christians who consider the Bible the inspired Word of God. 4) Christians committed to evangelism in their home country and mission work abroad that leads others to faith in Christ. (The author here relies closely on David Bebbington's famous fourfold definition of Evangelicals.)
OW also offers important info about world Christianity in general. Roman Catholics and Eastern Orthodox are declining as a percentage of the world's population, but Protestants and Anglicans are slowly growing. Mormons and Jehovah's Witnesses grew from less than 1 million in 1900 to over 45 million in 2000. Post-denominational churches and networks (often Charismatic) have exploded worldwide with a bewildering variety of Christian beliefs and practices. This Independent bloc of Christians grew from 7 million in 1900 to over 250 million in 2010. Evangelicals were only 80 million in 1960, exploded, numbered 420 million in 2000 and are now at 545 million worldwide. Pentecostals and Charismatics (beginning in the 1960s) went from zero in 1900 to over 300 million in 2000 and now number 426 million worldwide. More ancient forms of Christianity such as Eastern Orthodoxy declined significantly in the 20th century such that there are now less than 245 million affiliates worldwide and while Roman Catholicism claims 1.2 billion adherents, it might be closer to just a little over 1 billion affiliates at present given the mass conversion of Latin Americans to Pentecostalism. The Catholic Church often counts Latinos who become practicing Pentecostals as still part of the RC Church.
Given the paradigm shift that has taken place since the end of WW II, the success of Evangelical missions worldwide over the past two centuries, the decline of European Christianity, and the explosion of Christianity in the global south (Africa, Asia and Latin America) where various forms of Evangelical and Neo-Pentecostal Christianity continue to grow, often exponentially, this is an extremely helpful resource to have. This book confirms Philip Jenkins' assertion in "The Next Christendom: The Coming of Global Christianity" that Christianity is indeed no longer a northern, western, white or European religion. It is now a global phenomenon and is going to be as significant a factor for the world in the 21st century as re-energized Islam. Prognostications in the 20th century that Christianity and religion in general were going to fade into obsolescence have proved wrong. The vast majority of the world chooses to remain religious.