Islam Double in Number, While Christianity Decline Worldwide Except in Asia, Africa: Report

May 05, 2014 02:02 PM EDT

The global number of Christians has dropped, but Islam has doubled in members in the world, according to a report released by a Christian mission consultancy group. 

Project Care's Dick Slikker assembled the report, and in it he compared numbers of Christians and Muslims from 1900 to 2010.

Slikker's data shows that Christians made up of 34.5 percent of the world's population in 1900, but fell to 32.9 percent in 2010, while Muslims made up of 12.3 percent of the world's population in 1900, but rose to 22.5 percent in 2010. Also the number of Muslims exceeds those of Roman Catholics in the 1980s. 

In the time period studied, Christianity had the greatest rate of growth in Africa, increasing by 37 percent, but the faith had the greatest drop in Western Europe, decreasing by 30 percent. While Christian numbers have fallen in certain regions of the world, Islam has only grown in the 100+ years studied.  Growth and decline in the Christian churches has been divided across various regions, but the general pattern has been that more 'western' industrialised countries have seen their Christian populations decline, while developing countries are seeing increased growth.

Slikker believes the declining numbers of Christian is due to "increased materialism, secularism, rationalism, rejection of the notion of spiritual authority outside of oneself."

Considering Oceania, Slikker contends that while Christianity has declined by 3 percent between 1900 and 2010, the data also reveals that Christian numbers were rising in that region until 1970.

"It would be of considerable interest to identify the factors behind such developments to learn if any distinct lessons might be apparent," he said.

Meanwhile, Christian growth continue to rise in Asia, the only continent apart from Africa, the report stated. Christian population in Asia grew by six percent between 1900 and 2010, and the Islamic population grew by 10 percent.

Slikker hopes that the data can be used to understand what aid the growth of the faith and what hamper the spread of Christianity.