Author: Matt Martinich
The governments of some countries collect self-identified religious data on their populations as part of the census. This data provides important information on member activity rates and double affiliation as individuals indicate their identified religious group regardless of whether they remain on the records of the LDS Church or other denominations. In other words, census data provide the subjective religious affiliation of populations rather than reiterate statistical figures officially reported by religious groups. Many governments do not take a census on religious data in their respective countries, resulting in researchers relying on faith-reported membership totals to ascertain the religious demographic characteristics of a particular country or location.
Data on religious affiliation retrieved from censuses is valuable when assessing member activity rates in countries where census-reported religious data is available. Ascertaining the percentage of total church-reported members who self-affiliate as Latter-day Saints sheds insight into member activity rates as most inactive members no longer identify as Latter-day Saints on the census. In Chile, self-identified Latter-day Saints on the 2002 census accounted for 20% of the Church membership reported for 2002, although the census did not query the religious affiliation of individuals under the age of 15. This number is reasonably close to the estimated member activity rate of the Church in Chile at 12%. In Brazil, 199,645 persons identified themselves as Latter-day Saints on the 2000 census, just 26% of the number of members reported by the LDS Church at year-end 2000 and only a percent higher than the estimated member activity rate of Brazil (25%). In Mexico, the 2000 census counted 205,229 persons identifying as Latter-day Saints, just 23% of the number of members reported by the LDS Church at year-end 2000. The estimated activity rate for the Church in Mexico is 20-25%; identical to the percentage of self-affiliated members on the 2000 census. In Ireland, the 2006 census counted 1,237 self-identifying Latter-day Saints; 46% of membership reported by the Church at the time whereas the estimated member activity rate for Ireland is 35%. In Australia, the 2006 census reported 53,100 Latter-day Saints; 45% of nominal church membership notwithstanding member activity rates ranging from 25-30%. In New Zealand, the 2006 census tallied 43,539 Latter-day Saints; 45% of nominal membership on church records. LDS activity rates appear to range between 35-45% in New Zealand. In Samoa, the government reported that self-reported Latter-day Saints comprised 13.2% of the population whereas nominal membership constituted 36% of the national population. Member activity rates in Samoa are estimated at between 35% and 40%; nearly the same percentage as the percentage of membership who self reported on the census. In Tonga, the 2006 census found that 16.8% of national population identified as Latter-day Saint although membership comprised 45% of the national population. Between 30% and 35% of church membership appears active, slightly lower than the 38% of church membership that self reported as LDS on the census. In Fiji, 32% of nominal church membership self-reported as LDS on the 1996 census. The current estimated activity rate for the Church in Fiji is between 20% and 30%. In Iceland, government sources indicate that up to 75% of nominal LDS membership self-affiliates as Latter-day Saint notwithstanding an estimated member activity rate of 40%. These findings indicate that the percentage of nominal church membership which self affiliate on censuses as Latter-day Saint generally ranges within ten percentage points of estimated member activity rates.
Although census data number among one of the most objective and reliable methods for ascertaining member activity rates, there are several limitations to these data. First, individual countries vary in who they count as religious affiliates depending on age and family status. Religious status is identified by the head of the household for the entire family in some censuses. Children under a certain age are also not reported as religious adherents in some nations, such as children under five in the 2000 Mexican census, whereas children of member families are included in nominal and active membership statistics. Consequently many active youth may not be counted as Latter-day Saints on the census. Second, self-affiliation does not ensure active participation in church. Some inactive or less-active members continue to identify as Latter-day Saints but do not live church teachings and participate in services. Furthermore, not all active members are self affiliated on the census as is the case with many youth from part-member families.
Double affiliation occurs when two or more denominations claim the same individuals as members. This phenomenon has resulted in the summation of adherents reported by religious groups surpassing the total population of some countries such as in several Polynesian countries. Census data provides excellent insights into self-affiliation challenges for determining the true religious makeup of some countries. The LDS Church in Oceania experiences some of its most severe cases of double affiliation. In Tonga, official LDS membership statistics indicate that there were 53,449 members as of year-end 2006 whereas the 2006 Tongan census reported only 17,109 self-identified Latter-day Saints,  or 32% of membership reported by the LDS Church. At year-end 2011, nominal LDS membership constituted 56% of the national population but the most recent census statistic reports that Latter-day Saints comprise only 17% of the national population. 2006 Tongan census totals indicate that the population self-identifies as 37% Free Wesleyan, 17% Latter-day Saint, 16% Roman Catholic, 11% Free Church of Tonga, 7% Church of Tonga, 3% Tokaikolo, and 9% other denominations and religions. Nearly all census-reported Latter-day Saints in Tonga appear active considering the total number of Latter-day Saints on the 2006 census was one-third of the official church-reported membership at the time and member activity rates in Tonga are approximately 30-35% of nominal membership. Double affiliation also occurs in Latin America and Europe where self-reported Latter-day Saints on censuses constitute less than half of church-reported membership in virtually every country. Many nominal Latter-day Saints in these nations are converts who were not retained and are doubly affiliated with a traditional religious group such as the Catholic Church or another proselytizing group such as evangelicals, Seventh Day Adventists, and Jehovah's Witnesses.
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