Pew Research has just released a report on the size and distribution of the world's Muslim population.
A summary of the findings. . .
A comprehensive demographic study of more than 200 countries finds that there are 1.57 billion Muslims of all ages living in the world today, representing 23% of an estimated 2009 world population of 6.8 billion.
While Muslims are found on all five inhabited continents, more than 60% of the global Muslim population is in Asia and about 20% is in the Middle East and North Africa. However, the Middle East-North Africa region has the highest percentage of Muslim-majority countries. Indeed, more than half of the 20 countries and territories1 in that region have populations that are approximately 95% Muslim or greater.
More than 300 million Muslims, or one-fifth of the world’s Muslim population, live in countries where Islam is not the majority religion. These minority Muslim populations are often quite large. India, for example, has the third-largest population of Muslims worldwide. China has more Muslims than Syria, while Russia is home to more Muslims than Jordan and Libya combined.
Of the total Muslim population, 10-13% are Shia Muslims and 87-90% are Sunni Muslims. Most Shias (between 68% and 80%) live in just four countries: Iran, Pakistan, India and Iraq.