Assuming the death rate of Christians slows down from this weekend's horrific attacks, Pew Reasearch notes [2] that Muslims will outnumber the world's Christians by 2070...
[2]
As of 2010, 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.
But, if current demographic trends continue... Islam will nearly catch up by the middle of the 21st century.
[3]
Between 2010 and 2050, the world’s total population is expected to rise to 9.3 billion, a 35% increase.
[4]
Over that same period, Muslims – a comparatively youthful population with high fertility rates – are projected to increase by 73%. The number of Christians also is projected to rise, but more slowly, at about the same rate (35%) as the global population overall.
As a result, according to the Pew Research projections, by 2050 there will be near parity between Muslims (2.8 billion, or 30% of the population) and Christians (2.9 billion, or 31%), possibly for the first time in history.
