Question: What percentage of the world population identifies as Christian?

Christian population growth


Christian population growth is the population growth of the global Christian community. According to a 2011 Pew Research Center survey, there were 2.19 billion Christians around the world in 2010, more than three times as many as the 600 million recorded in 1910. However,  this rate of growth is slower than the overall population growth over the same time period.[1] According to a 2015 Pew Research Center study, by 2050, the Christian population is expected to be 3.0 billion.[2]
The average Christian fertility rate is 2.7 children per woman, which is higher than the global average fertility rate of 2.5. Globally, Christians were only slightly older (median age of 30) than the  global average median age of 28 in 2010. According to Pew Research religious switching is projected to have a modest impact on changes in the Christian population.[3] According to the World Christian Encyclopedia, approximately 2.7million converting to Christianity annually from another religion, World Christian Encyclopedia also cited that Christianity rank at first place in net gains through religious conversion.[4] While according to "The Oxford Handbook of Religious Conversion", approximately 15.5million converting to Christianity annually from another religion, while approximately 11.7million leave Christianity annually, and most of them become irreligious, resulting in a net gain of 3.8 million.[5] Christianity earns about 65.1 million people annually due to factors such as birth rate, religious conversion and migration, while losing 27.4 million people annually due to factors such as death rate, religious apostasy and immigration. Most of the net growth in the numbers of Christians is in Africa, Latin America and Asia.[6]
Summary

Christian fertility rate is 2.7 children per woman, which is higher than the global average fertility rate of 2.5. Globally, Christians were only slightly older (median age of 30) than the  global average median age of 28 in 2010. According to Pew Research religious switching is projected to have a modest impact on changes in the Christian population.[3]
According to the World Christian Encyclopedia, approximately 2.7million converting to Christianity annually from another religion, World Christian Encyclopedia also cited that Christianity rank at first place in net gains through religious conversion.[8] While according to "The Oxford Handbook of Religious Conversion", approximately 15.5million converting to Christianity annually from another religion, while approximately 11.7million leave Christianity annually, and most of them become irreligious, resulting in a net gain of 3.8 million.[9] Christianity earns about 65.1 million people annually due to factors such as birth rate, religious conversion and migration, while losing 27.4 million people annually due to factors such as death rate, religious apostasy and immigration. Most of the net growth in the numbers of Christians is in Africa, Latin America and Asia.[10]
Fertility rate
The Christian fertility rate has varied throughout history, as with other fertility figures. The Christian fertility rate also varies from country to country. In the 20-year period from 1989–2009, the average world fertility rate decreased from 3.50 to 2.58, a fall of 0.92 children per women, or 26%. The weighted average fertility rate for Christian nations decreased in the same period from 3.26 to 2.58, a fall of 0.68 children per women, or 21%. The weighted average fertility rate for Muslim nations decreased in the same period from 5.17 to 3.23, a fall of 1.94 children per women, or 38%. While Muslims have an average of 3.1 children per woman—the highest rate of all religious groups—Christians are second, with 2.7 children per woman.[2]
The gap in fertility between the Christian- and Muslim-dominated nations fell from 67% in 1990 to 17% in 2010.  If the trend continues, the Muslim and Christian fertility rates will converge in around 2050.[2]

Conversion

Pew Research estimates that 40 million people are expected to convert to Christianity between 2010-2050, and 106 million people are expected to leave Christianity during that period (resulting in a net loss of 66 million).[3] This is in contrast to most other religions, including Islam and Hinduism, where the number converting in is roughly similar to the number converting out.[3]
According to the World Christian Encyclopedia, approximately 2.7 million people convert to Christianity annually from another religion, with Christianity ranking first in net gains through religious conversion.[12]
Studies estimate significantly more people have converted from Islam to Christianity in the 21st century than at any other point in Islamic history.[13] Conversion to Christianity has also been well documented, and reports estimate that hundreds of thousands of Muslims convert to Christianity annually. Significant numbers of Muslims converts to Christianity can be found in Afghanistan, Albania,[14] Azerbaijan,[15][16] Algeria,[17] Belgium,[18] Bulgaria,[19][20] France,[21] Germany,[22] Indonesia,[23] Iran,[24][25][26][27] Kazakhstan,[28] Kyrgyzstan,[29] Malaysia,[30] Morocco,[31][32] Netherlands,[33] Russia,[34] Saudi Arabia,[35] Tunisia,[36] Turkey,[37][38][39][40] Kosovo,[41] The United States[42] and Central Asia etc.[43][44] Many of the Muslims who convert to Christianity faces social rejection or imprisonment and sometimes murder or penalty, for becoming Christians.[45]
Data from the Pew Research Center show that, as of 2013, about 1.6 million adult American Jews identify themselves as Christians; most are Protestant.[46][47][48] According to the same data, most of this group were raised as Jews or are Jews by ancestry.[47] Data from 2013, show that 64,000 Argentine Jews identify themselves as Christians.[49] According to 2012 study 17% of Jews in Russia identify themselves as Christians.[50][51]
Conversion into Christianity has significantly increased among Korean,[52] Chinese,[53] and Japanese in the United States.[54] In 2012, the percentage of Christians in these communities were 71%, 30% and 37% respectively.[55]
Due to conversion, the number of Chinese Christians has increased significantly; from 4 million before 1949 to 67 million in 2010.[56][57]
Due to conversion, Christianity has grown in South Korea, from 2.0% in 1945[58] to 29.3% in 2010.[56]
By branches
Roman Catholic Church

Church membership in 2007 was 1.147 billion people[59] (17% of the global population at the time), increasing from the 1950 figure of 437 million[60] and 654million in 1970.[61][62] On 31 December 2008, membership was 1.166 billion, an increase of 11.54% over the same date in 2000,[63][63] and slightly greater than the rate of increase of the world population (10.77%). The increase was 33.02% in Africa,[63] but only 1.17% in Europe. It was 15.91% in Asia, 11.39% in Oceania, and 10.93% in Americas.[63] As a result, Catholics were 17.77% of the total population in Africa, 63.10% in Americas, 3.05% in Asia, 39.97% in Europe, 26.21% in Oceania, and 17.40% of the world population. Of the world's Catholics, the proportion living in Africa grew from 12.44% in 2000 to 14.84% in 2008, while those living in Europe fell from 26.81% to 24.31%. However, Catholic numbers have grown in Scandinavia where the Catholics in Nordic dioceses have tripled or even quadrupled. For example, in Denmark, Norway, Sweden and Finland, 330,000 Catholics have now registered in their dioceses.[64] [65] Membership of the Catholic Church is attained through baptism,[66] and from 1983 to 2009, if someone formally left the Church, that fact was noted in the register of the person's baptism.
Monsignor Vittorio Formenti, who compiles the Vatican's yearbook, said in an interview with the Vatican newspaper L'Osservatore Romano that "For the first time in history, we are no longer at the top: Muslims have overtaken us."  He said that Catholics accounted for 17.4 percent of the world population—a stable percentage—while Muslims were at 19.2 percent. "It is true that while Muslim families, as is well known, continue to make a lot of children, Christian ones on the contrary tend to have fewer and fewer," the monsignor said,[67], though Africa and parts of Asia are the exception. If the UN report in 2018 is on target, Africa's population will grow to 4.5 billion by 2100, adding to all African religious groups.[68] Muslims in 2010 represented as much as 23.4% of the total world population and this is expected to increase to 26.3% by 2030.[69] The global Catholic population is projected to grow to 1.63 billion in 2050,[70] but by that time Islam will have nearly 3 billion adherents.
Eastern Orthodoxy

Protestantism

According to Mark Jürgensmeyer of the University of California, popular Protestantism is one of the most dynamic religious movements in the contemporary world.[71] Changes in worldwide Protestantism over the last century have been significant.[72] Since 1900, due primarily to conversion, Protestantism has spread rapidly in Africa, Asia, Oceania and Latin America.[73]
There are more than 900 million Protestants worldwide,[1][74][75][76][77][78][79] among approximately 2.4 billion Christians.[74][80][81][82] In 2010, a total of more than 800 million included 300 million in Sub-Saharan Africa, 260 million in the Americas, 140 million in Asia-Pacific region, 100 million in Europe and 2 million in Middle East-North Africa.[1] Protestants account for nearly forty percent of Christians worldwide and more than one tenth of the total human population.[1]
Protestantism is growing in Africa,[83][84] Asia,[84][85] Latin America,[84][86] Muslim world,[87] and Oceania,[88] while remaining stable or declining in Anglo America[88] and Europe,[77][89] with some exceptions such as France,[90] where it was eradicated after the abolition of the Edict of Nantes by the Edict of Fontainebleau and the following persecution of Huguenots, but now is claimed to be stable in number or even growing slightly.[90] According to some, Russia is another country to see a Protestant revival.[91][92][93]
By country

According to the Carnegie Endowment for International Peace, the World Christian Database as of 2007 estimated the six fastest-growing religions of the world to be Islam (1.84%), the Bahá'í Faith (1.7%), Sikhism (1.62%), Jainism (1.57%), Hinduism (1.52%) and Christianity (1.32%). High birth rates were cited as the reason for the growths.[94]
The U.S. Center for World Mission stated a growth rate of Christianity at 2.3% for the period 1970 to 1996 (slightly higher than the world population growth rate at the time).  This increased the claimed percentage of adherents of Christianity from 33.7% to 33.9%.[95]
The World Christian Database as of 2007 estimated the growth rate of Christianity at 1.32%. High birth rates and conversions were cited as the main reasons.[96]
Using data from the period 2000–2005 the 2006 Christian World Database estimated that by number of new adherents, Christianity was the fastest growing religion in the world with 30,360,000 new adherents in 2006. This was followed by Islam with 23,920,000 and Hinduism with 13,224,000 estimated new adherents in the same period.[97]
According to 2011 Pew Research Center survey, there are 2.18 billion Christians around the world in 2010, up from about 600 million in 1910.[1]
According to 2015 Believers in Christ from a Muslim Background: A Global Census study estimates 10,283,700 Muslim converted to Christianity around the world.[87]
On April 2, 2015, the Pew Research Center published a Demographic Study about “The Future of World Religions: Population Growth Projections, 2010-2050" with projections regarding Christianity.[98] The projection begins with 2010 statistics when "Christianity was by far the world’s largest religion, with an estimated 2.2 billion adherents, nearly a third (31%) of all 6.9 billion people on Earth. Islam was second, with 1.6 billion adherents, or 23% of the global population.”[98]
Projected growth of Christianity by 2050
Some of the projections are as follows:[99]
Over the 2010-2050 period, Christians will remain the largest religious group with 34.1% of the world’s population. However, Islam will grow faster and become 29.7% of the world’s population. Therefore, by 2050 there will be 2.8 billion Muslims compared to 2.9 billion Christians.
“In the United States, Christians will decline from more than three-quarters of the population in 2010 to two-thirds in 2050.”
“Four out of every 10 Christians in the world will live in sub-Saharan Africa.”
Reasons given for the projected growth
Some of the reasons the Study gives are as follows:[98]
The change in the world’s religious is “driven primarily by differences in fertility rates and the size of youth populations among the world’s major religions, as well as by people switching faiths.”
Fertility rates. “Religions with many adherents in developing countries, where birth rates are high, and infant mortality rates generally have been falling, are likely to grow quickly.” Therefore, much of the growth of Christianity is projected to take place in sub-Saharan Africa. Globally, Christians have a birth rate of 2.7 children per woman. But Muslims have a higher rate, namely, an average of 3.1 children per woman. This differential is one of the reasons that the Muslim population is growing faster than the Christian.
Size of youth population. “In 2010, more than a quarter of the world’s total population (27%) was under the age of 15.” Christian youth under 15 were the same as the 27% global average. But an even higher percentage of Muslims (34%) were younger than 15. This higher youth population is one of the reasons that from 2010-2050 Muslims are projected to grow faster than Christians.
Size of old population. In 2010, “11% of the world’s population was at least 60 years old,”  14% of the Christian population was over 60 years old, but only 7% of Muslims were over 60. This is another reason that Muslims are projected to grow faster than Christians.
Switching. A loss of 66 million Christians is projected to come through switching. Most of the loss is projected to come from Christians “joining the ranks of the religiously unaffiliated.”
The whole Pew Research Center can be read by clicking 
Africa

Christianity has been estimated[1] to be growing rapidly in South America, Africa, and Asia.[82] In Africa, for instance, in 1900, there were only 8.7 million[1] adherents of Christianity; now there are 390 million,[1] and it is expected that by 2025 there will be 600 million Christians in Africa.[1] The number of Catholics in Africa has increased from one million in 1902 to 329,882,000.[1] There are now 1.5 million churches whose congregations account for 46 million people.
A 2015 study estimates 2,161,000 Muslim Africans that convert to Christianity.[87]
 Algeria

Converts to Christianity may be investigated and searched by the authorities.[100] Conversions to Christianity have been most common in Kabylie, especially in the wilaya of Tizi-Ouzou.[101]
A 2015 study estimates 380,000 Muslims converted to Christianity in Algeria.[87]
 Ethiopia

A 2015 study estimates 400,000 Muslims converted to Christianity in Ethiopia.[87]
 Libya

A 2015 study estimate some 1,500 believers in Christ from a Muslim background living in the country.[102]
 Morocco

On 27 March 2010, the Moroccan magazine TelQuel stated that thousands of Moroccans had converted to Christianity. Pointing out the absence of official data, Service de presse Common Ground, cites unspecified sources that stated that about 5,000 Moroccans became Christians between 2005 and 2010.[103] According to the International Religious Freedom Report for 2014 estimate that there may be as many as 8,000 Christian citizens throughout the country, but many reportedly do not meet regularly due to fear of government surveillance and social persecution.[104]
According to different estimates, there are about 25,000-45,000 Moroccan Christians of Berber or Arab descent mostly converted from Islam. Other sources give a number of a bit more than 1,000.[105] A popular Christian program by Brother Rachid has led many former Muslims in North Africa and the Middle East to convert to Christianity. His programs have been credited with assisting in the conversion of over 150,000 former Muslims to Christianity in Morocco.[106]
 Nigeria

The percentage of Christians in Nigeria grew from 21.4% in 1953 to 48.2% in 2003.[56] This is due to the high number of missionaries in Nigeria.
ِA 2015 study estimates some 600,000 believers in Christ are from a Muslim background living in Nigeria.[107]
 South Africa

In South Africa, Pentecostalism has grown from 0.2% in 1951 to 7.6% in 2001.[108]
 Tunisia

International Religious Freedom Report for 2007 estimate thousands of Tunisian Muslims who convert to Christianity.[36]
Asia

 Afghanistan

The United States Department of State estimated the numbers of the Muslim Afghan who convert to Christianity between 500-8,000.[109]
 Azerbaijan

According to reports there is about 5,000 ethnic Azerbaijani Protestant community most of them came from Muslim backgrounds.[15][16]
 Bangladesh

A 2015 study estimates some 130,000 Christians from a Muslim background residing in the Bangladesh, though not all are necessarily citizens.[29]
 China

In recent years, the number of Chinese Christians has increased significantly, particularly since the easing of restrictions on religious activity during economic reforms in the late 1970s; Christians were 4 million before 1949 (3 million Catholics and 1 million Protestants), and are reaching 67 million today.[1][57] Various statistical analyses have found that between 2% and 4% of the Chinese identify as Christian.
Christianity is reportedly the fastest growing religion in China with average annual rate of 7%.[110]
 India

A 2015 study estimates some 40,000 Christian believers from a Muslim background in the country, most of them belonging to some form of Protestantism.[111]
 Indonesia

According to the World Christian Encyclopedia, between 1965-1985 about 2.5 million Indonesian converted from Islam to Christianity.[112]
According to Believers in Christ from a Muslim Background: A Global Census study found that between 1960-2015 about 6.5 million Indonesian Muslims convert to Christianity.[87]
Some reports also show that many of the Chinese Indonesians minority convert to Christianity.[113][114]  Demographer Aris Ananta reported in 2008 that "anecdotal evidence suggests that more Buddhist Chinese have become Christians as they increased their standards of education".[115]
 Iran

Christianity is reportedly the fastest growing religion in Iran with an average annual rate of 5.2%.[116] A 2015 study estimates between 100,000 and 500,000 believers Christians from a Muslim background living in Iran, most of them evangelical Christians.[117]
 Israel

Several thousand Israelis practice Messianic Jewish denominations, which are often considered as Christian sects. The Messianic Jews usually combine Jewish and Christian practices, but do recognize Jesus as the Messiah. There are no exact numbers on those communities, but it is believed that several hundred to several thousand ethnic Jews belong to this tradition as well as several thousand Israelis of mixed ancestry (mostly mixed Jewish and Slavic).
The Christian population in Israel has increased significantly with the immigration of many mixed families from the former Soviet Union (1989-late 1990s).
 Japan

Christianity is one of several minority religions in Japan, accounting for about 0.5 percent of the population.[118][119][120]
 Kazakhstan

In spite of persecution of converts from Islam to Christianity, a 2015 study estimates some 50,000 believers in Christ from a Muslim background residing in the country. [121]
 Kyrgyzstan

A 2015 study estimates some 19,000 Christians from a Muslim background residing in the country, though not all are necessarily citizens of Kyrgyzstan. [122]
 Malaysia

According to a Hindu organization, 130,000 people converted from Hinduism to Christianity between 1965 and 1990. Around 97,000 joined the Methodist Church and the rest mostly joined various Protestant denominations, with 2,500 joining the Catholic Church.[123]
There is no well researched agreement on the actual number of Malaysian Muslim converts to Christianity in Malaysia.[30] But according to Tan Sri Dr Harussani Zakaria, they are 260,000.[30]
 Mongolia

According to the Christian missionary group Barnabas Fund, the number of Christians in Mongolia grew from just four in 1989 to around 40,000 as of 2008.[124]
  Saudi Arabia

A 2015 study estimates 60,000 Muslims converted to Christianity in Saudi Arabia.[87]
 Singapore

The percentage of Christians among Singaporeans increased from 12.7% in 1990 to 17.5% in 2010.[125]
 South Korea

In South Korea, Christianity has grown from 20.7% in 1985 to 29.5% in 2005 according to the World Christian Database.[108][126]
 Tajikistan

In spite of opposition in relation to conversion from Islam to Christianity, a 2015 study estimates some 2,600 Christians with Muslim backgrounds reside in the country. [127]
 Turkey

According to the newspaper, "Milliyet" reports 35,000 Muslim Turks convert into Christianity in 2008.[128] A 2015 study estimates some 4,500 believers in Christ from a Muslim background in Turkey, most of them Turks.[129] The ethnic Turkish Protestant Christian community in Turkey number about 4,000-5,000[130] adherents most of them came from Muslim Turkish background.[131][132][133][134]
 Uzbekistan

A 2015 study estimates some 10,000 believers in Christ from a Muslim background in the country, most of them belonging to some sort of evangelical or charismatic Protestant community.[135]
 Vietnam

The US Department of State estimates that Protestant Christianity may have grown 600% over the last decade in Vietnam.[136]
Europe

 Albania

A 2015 study estimated some 13,000 followers of Christ from a Muslim background, though it is not clear to which Christian churches these people had converted. [137]
 Belgium

Reports estimated that "many" Muslims convert every year to Christianity in Belgium.[18]
  Bulgaria

Reports estimated that thousands of Muslims (mostly Bulgarian Turks) convert every year to Christianity in Bulgaria.[19][20] A 2015 study estimates 45,000 Christian believers from a Muslim background in the country, most of them belonging to some form of Protestantism.[111]
  Denmark

There are around 4,000 Christians who have converted from a Muslim background in the country, most of them belonging to some form of Protestantism.[138]
 France

Protestants have increased as a percentage of total population from 1% in 1987 to 3% in 2009.[139]
Reports form Le Monde estimated that 15,000 Muslims convert every year to Christianity.[21]
 Germany

Reports estimated that thousands of Muslims convert every year to Christianity in Germany.[22]
  Kosovo

Reports estimated that hundreds of Muslims convert every year to Christianity in Kosovo.[140]
 Norway

It is estimated that Orthodoxy is the fastest growing religious faith in Norway, due to immigration from other countries, with a growth rate from 2000 to 2009 at 231.1%.[141]
 Netherlands

Reports estimated that 4,500 Muslims have converted to Christianity in the Netherlands.[33]
 Russia

According to Roman Silantyev the executive secretary of the Inter-religious Council in Russia, about 2 million Muslims in Russia have converted to Christianity between during the last fifteen years while only 2,500 Russians converted to Islam.[34]
According to a 2012 study, 17% of Jews in Russia identify themselves as Christians.[50][51]
 Sweden

In recent years a number of Swedish Muslims have converted from Islam to the Church of Sweden, most noticeably by Iranians, but also by Arabs and Pakistanis. [142]
 United Kingdom

A 2015 study estimated some 25,000 believers in Christ from a Muslim background, most of whom belong to an evangelical or Pentecostal community. [143]
North America

 Canada

According to the 1991/2001/2011-Census, the number of Christians in Canada has decreased from 22.5 million to 22.1 million.
 United States

The United States government does not collect religious data in its census. The survey below, the American Religious Identification Survey (ARIS) 2008, was a random digit-dialed telephone survey of 54,461 American residential households in the contiguous United States. The 1990 sample size was 113,723; 2001 sample size was 50,281.
Adult respondents were asked the open-ended question, "What is your religion, if any?" Interviewers did not prompt or offer a suggested list of potential answers. The religion of the spouse or partner was also asked. If the initial answer was "Protestant" or "Christian" further questions were asked to probe which particular denomination. About one third of the sample was asked more detailed demographic questions.
Among the Asian population in the United States, conversion into Christianity is significantly increasing among Korean, Chinese, and Japanese.[144] By 2012 the percentage of Christians in these communities was 71%, 31%, and 38% respectively.[55]
Data from the Pew Research Center states that, as of 2013, about 1.6 million adult American Jews identify themselves as Christians, most as Protestants.[46][47][48] According to the same data, most of the Jews who identify themselves as some sort of Christian (1.6 million) were raised as Jew or are Jews by ancestry.[47]
According to Pew Research, Christianity loses more people than it gains from religious conversion. It found that 23% of Americans raised as Christians no longer identified with Christianity, whereas 6% of current Christians were converts.[145] This was in contrast to Islam in America, where the number of people who leave the religion is roughly equal to the number who convert to it.[145] The National Catholic Register claims that in 2015 there were 450,000 American Muslim converts to Christianity and that 20,000 Muslims convert to Christianity annually in the United States.[146]
Religious Self-Identification of the U.S. Adult Population: 1990, 2001, 2008[147]
Figures are not adjusted for refusals to reply; investigators suspect refusals are possibly more representative of "no religion" than any other group.

Highlights:[147]
The ARIS 2008 survey was carried out during February–November 2008 and collected answers from 54,461 respondents who were questioned in English or Spanish.
The American population self-identifies as predominantly Christian but Americans are slowly becoming less Christian.
86% of American adults identified as Christians in 1990 and 76% in 2008.
The historic Mainline churches and denominations have experienced the steepest declines while the non-denominational Christian identity has been trending upward particularly since 2001.
The challenge to Christianity in the United States does not come from other religions but rather from a rejection of all forms of organized religion.
34% of American adults considered themselves "Born Again or Evangelical Christians" in 2008.
The U.S. population continues to show signs of becoming less religious, with one out of every seven Americans failing to indicate a religious identity in 2008.
The "Nones" (no stated religious preference, atheist, or agnostic) continue to grow, though at a much slower pace than in the 1990s, from 8.2% in 1990, to 14.1% in 2001, to 15.0% in 2008.
Asian Americans are substantially more likely to indicate no religious identity than other racial or ethnic groups.
One sign of the lack of attachment of Americans to religion is that 27% do not expect a religious funeral at their death.
Based on their stated beliefs rather than their religious identification in 2008, 70% of Americans believe in a personal God, roughly 12% of Americans are atheist (no God) or agnostic (unknowable or unsure), and another 12% are deistic (a higher power but no personal God).
America's religious geography has been transformed since 1990. Religious switching along with Hispanic immigration has significantly changed the religious profile of some states and regions. Between 1990 and 2008, the Catholic population proportion of the New England states fell from 50% to 36% and in New York it fell from 44% to 37%, while it rose in California from 29% to 37% and in Texas from 23% to 32%.
Overall the 1990–2008 ARIS time series shows that changes in religious self-identification in the first decade of the 21st century have been moderate in comparison to the 1990s, which was a period of significant shifts in the religious composition of the United States.
See also
Muslim population growth
Claims to be the fastest-growing religion
Christian views on contraception
Christian mission
Christianity by country
Christian emigration