When demographers attempt to forecast changes in the size of a population, they typically focus on four main factors: fertility rates, mortality rates (life expectancy), the initial age profile of the population (whether it is relatively old or relatively young to begin with) and migration. In the case of religious groups, a fifth factor is switching – how many people choose to enter and leave each group, including how many become unaffiliated with any religion.
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According to an article on World Economic Form, Islam is growing faster than any other religion, according to a study by the Pew Research Center. In fact, most of the world’s major religious groups are expected to rise in absolute numbers by 2050, the research finds, with Islam set to overtake Christianity and become the world’s dominant religion by 2070.
