rate at the time). This increased the claimed percentage of adherents of Christianity from 33.7% to 33.9%. 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. 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. According to 2011 Pew Research Center survey, there are more than 2.2 billion Christians around the world in 2010, up from about 600 million in 1910. The 2015 "Believers in Christ from a Muslim Background: A Global Census" estimates 10,283,700 Muslim converted to Christianity around the world. On 2 April 2015, the Pew Research Center published a Demographic Study about "The Future of World Religions: Population Growth Projections, 2010-2050" with projections regarding Christianity. 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." Projected growth of Christianity by 2050 Some of the projections are as follows: Over the 2010-2050 period, Christians will remain the largest religious group with 30.7% 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: 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