Overview

• Between 2010 and 2020, Christianity’s share of the global population fell by 1.8 percentage points even as its total adherents climbed to 2.3 billion.
• Islam’s global share rose by 1.8 points to 25.6 percent, underpinned by a median age of 24 and higher birthrates in key regions.
• Nearly a quarter of people worldwide now identify as unaffiliated with any religion, a rise largely propelled by former Christians and concentrated in China.
• Sub-Saharan Africa has overtaken Europe as the region with the largest share of Christians, reflecting high fertility and a youthful demographic profile.
• Pew Research Center projects that if current trends continue, Islam could become the world’s largest religion within coming decades.