I'm trying to determine whether or not a majority of Orthodox are on the Old or on the New Calendar. I don't need numbers for this question, but I do need names.
Who are on the Old, and who are on the New?
This wiki claims that the "churches of Constantinople, Alexandria, Antioch, Greece, Cyprus, Romania, Poland, Bulgaria, and most of the Orthodox Church in America." are on the New Calendar.
Ok, good start. Is that comprehensive?
This wiki page states that "Those Orthodox Churches which remain in full communion with the New Calendarists and yet continue to use the Julian calendar, include the Orthodox Church of Jerusalem, the Russian Orthodox Church, the Serbian Orthodox Church, and the Georgian Orthodox Church. (The Julian calendar is also used by the Russian Orthodox Church Outside of Russia which has reunited with the Russian Orthodox Church.) Mount Athos subordinate to the Patriarchate of Constantinople also follows the Julian Calendar."
Ok, not comprehensive. If the Wiki page is accurate, the Old Calendar churches include Jerusalem, Moscow, Serbian, Georgian, ROCOR, Mount Athos, and all other Old Calendar churches who are not in communion with Constantinople.
I don't think it is comprehensive, however, as there is a Palestinian Orthodox church in my area that is in communion with Constantinople (and under their authority) who is on the Old Calendar.
I'm also unsure of how to obtain a list of Orthodox churches which are not in communion with Constantinople and who are on the Old Calendar.