The Pew Research Center report, The Changing Global Religious Landscape, issued in April, 2017, updates Pew's earlier 2015-2050 world religious population projection. The subtitle notes: "Babies born to Muslims will begin to outnumber Christian births by 2035..." Moreover, "Muslims are projected to be the world’s fastest-growing major religious group in the decades ahead...and signs of this rapid growth already are visible. In the period between 2010 and 2015, births to Muslims made up an estimated 31% of all babies born around the world – far exceeding the Muslim share of people of all ages in 2015 (24%)."
The world’s Christian population also has continued to grow, but more modestly. In recent years, 33% of the world’s babies were born to Christians, which is slightly greater than the Christian share of the world’s population in 2015 (31%).
The report includes projections from 2015 to 2060. "Between 2015 and 2060, the world’s population is expected to increase by 32%, to 9.6 billion. Over that same period, the number of Muslims – the major religious group with the youngest population and the highest fertility – is projected to increase by 70%. The number of Christians is projected to rise by 34%, slightly faster than the global population overall yet far more slowly than Muslims."
Jewish population estimates: "Jews, the smallest religious group for which separate projections were made, are expected to grow by 15%, from 14.3 million in 2015 to 16.4 million worldwide in 2060." Summary table of world's religious populations growth 2015-2060 on page 10 of the "Full Report" notes that Jews represent 0.2% of all world religious group members in 2015 and are expected to remain about 0.2% of the 2060 world religious group population.
Jewish Definition Used.
Jewish estimates provided are essentially Jews-by-religion (JBR), and do not include Jews who may not identify as Jewish by religion, but may identify for other reasons (family background, secular Jewish, etc.):
Jews: "The projections in this report are based on estimates of people who self-identify as Jewish when asked about their religion on national censuses and large-scale surveys. The figures do not include “cultural” or “ethnic” Jews – people who have Jewish ancestry and may consider themselves at least partially Jewish but who do not describe their current religion as Jewish. The worldwide figures in this report could be larger if a broader definition (such as having a Jewish grandparent) or smaller if a tighter definition (such as an unbroken line of matrilineal Jewish descent) were imposed." (Appendix E, "Defining Religious Groups," p.2)
DataBank users should note that the Jewish-by-religion definition and estimates used by Pew in this report are the same as those used in Pew's American Religious Landscape reports. They differ from the estimates reported in the Pew 2013 Portrait of Jewish Americans, which include secular Jews who identify with being Jewish, but not as a religion.