2005 Annual Megacensus of Religions

▪ 2006

      Statistical data about religions and churches have been generated from various sources at least since 1750, and the amount of data available has been growing quickly. In addition to the religious groups' own statistics, much of the information comes from decennial governmental censuses; about half the countries of the world ask their populations to state their religions, if any. The United States has never asked a religious question in the federal censuses, which have been conducted since 1790. In its 2000 census the British government introduced a religion question for the first time since 1851, acknowledging that the information is valuable for enumerating and serving the social needs of ethnic minorities. Less-developed countries began to drop religion questions owing to the high cost of including them, but this trend seems to have been reversing in recent years. A second major source of church membership data is the decentralized censuses taken by many religious headquarters. Almost all 37,000 Christian denominations ask statistical questions each year on at least some of 180 major religious subjects. All Roman Catholic bishops, for instance, are required to answer 141 statistical questions about their activities over the previous 12 months. Each year about 27,000 new books on the religious situation in a single country, as well as some 9,000 printed annual yearbooks or official handbooks, appear in print. Although not centralized or coordinated, these publications are the third significant source of data for the megacensus of world religion. The two tables below are the result of a combination and synthesis of these data around the major characteristic, namely individuals' religious profession and/or affiliation. The first table (Worldwide Adherents of All Religions, Mid-2005) summarizes worldwide adherents by the 19 major or largest religions. The second table (Religious Adherents in the United States of America, 1900-2005) goes into more detail for the United States.

David B. Barrett, Todd M. Johnson, Peter F. Crossing

* * *