By Kent H. Roberts
© 2011 Kent H. Roberts

---

The Church of Jesus Christ of Latter-day Saints, commonly known as the “Mormons,” is frequently identified as one of the fastest growing churches in the United States. Official membership statistics show a six fold increase in membership of the LDS church from 1950 to 2010, while the US population only doubled and the population of Utah, the center of the church, has only quadrupled during that time. This growth rate draws attention to the LDS church. As a missionary organization, the church certainly encourages this positive attention. The attention also increases the political influence of the church which is significant in Washington DC and more than significant in the Western states of Utah, Idaho, Nevada, Arizona and California.

For the past twenty years, Professors Barry A. Kosmin and Ariela Keysar have conducted the American Religious Identification Survey (ARIS). Using standard statistical methods and the same question: “What is your religion, if any?”, they have been determining which religious groups Americans actually belong to and in what numbers. The research is not directed at the LDS church or any other particular denomination. The Survey has been conducted in 1990, 2001 and 2008.¹

The ARIS raises significant questions about the true number of persons in the USA who understand themselves to be members of the LDS church. Briefly stated, at the beginning of 1990, the LDS church claimed a membership in the USA of 4,175,400, while the ARIS showed that, during 1990, 2,487,000 Americans claimed to be Mormons, a 40% difference. At the beginning of 2001, the LDS church claimed a membership in the USA of 5,208,827, while the ARIS showed that, during 2001, 2,697,000 Americans claimed to be Mormons, a 48% difference. Finally, at the end of 2008, the LDS church claimed a membership in the USA of 5,974,041, while the ARIS showed that, during the year, 3,158,000 Americans claimed to be Mormons, a 47% difference.²

This paper places the official statistics of the LDS church and the ARIS results in juxtaposition, attempts to provide some historical context and suggests additional work by persons who may have a stake in the result.

Comparison of ARIS with Official Statistics

Figure 1 below places the ARIS figures in the context of the official LDS membership statistics for the USA since 1950.

Figure 1

The tabular data is as follows: ^{3 4}

There is a grey shaded wedge indicated on Figure 1. This represents the rate of population growth in the USA and Utah between 1950 and 2010. This is added to indicate the effect of population growth over the post World War II period. The upper line of the wedge represents the rate of growth in Utah which was approximately 300%, from 688,862 in 1950 to 2,763,885 in 2010 and the lower line of the wedge represents the rate of growth in the USA which was approximately 100%, from 151,325,798 in 1950 to 308,745,538 in 2010, according to the US Census Bureau.⁵ In 1950, 47% of the total USA membership of the LDS Church lived in Utah.⁶ By 1980, the percentage of the US Mormon population in Utah was 29%.⁷ By 2000, the Utah portion was 31%.⁸

Observations

The first observation is that there is a significant difference between the number of Americans that the LDS church claims are Mormons and the number of Americans who claim to be Mormons. This raises a number of questions discussed below.

The second observation is that if the population growth rate wedge is anchored with the 1950 church population, the ARIS results are comfortably explained by population growth in the relevant regions. This would tend to support the validity of the ARIS results while explaining the perceptible growth of the LDS church.

The third observation is that, if the ARIS results are projected backward in time, they nearly intersect with the 1950 and 1960 official LDS statistics. The deviation between the official statistics and the actual and projected ARIS results appears to begin in the 1960s and accelerates during the 1970s. This period corresponds with two vigorous missionary drives within the LDS church – the “Every Member a Missionary” program under President David O. McKay (1951 – 1970) and the “Lengthen Your Stride” program under President Spencer W. Kimball (1973 – 1985).

Questions

For scholars, the following questions are presented: When, how and why did this overstatement of LDS membership in the USA develop? Is the variation between ARIS and official statistics found in any other religious group in the USA?

For LDS church operational managers, the following questions are presented: How does the church insure that its true population is being measured? Further, are there incentives in the system to overstate the church population? Is a similar overstatement happening in areas outside the United States of America? Professor Lanier Britsch documented an example in the French Polynesian Mission in the 1920s where the church population figures were revised downward by 38% following “a careful census.”⁹ D. Michael Quinn documented an aggressive program in the British Mission in the 1960s first to increase the number of members followed by an aggressive program to remove non-believers from the church rolls.¹⁰ In the decade just concluded, the number of stakes—the local LDS administrative unit—in Chile was reduced 36%, from 115 to 74, after the 2002 government census revealed that 103,735 persons identified themselves as Mormon in contrast to the 509,592 members that the LDS church claimed at the end of 2000.¹¹ The actions in Chile were reported in the May 2006 issue of the Salt Lake City Messenger. It is worth noting that the LDS church currently (October 2011) claims a Chilean membership of 563,689.¹²

For LDS spiritual leaders, the question is: Why is there such a significant drop-off in affiliation with the church after baptism? A person becomes a member of the LDS church through adult baptism (actually, the eighth birthday is the minimum age). Baptism is delayed so that the candidate can make the decision in his or her own judgment. A member who does not attend regularly is commonly referred to as “inactive.” One who rejects the decision made at baptism into the LDS church is considered an “apostate.” The ARIS question addresses whether one is affiliated with a faith tradition, not the level of activity within that faith. If the official LDS church statistics represent primarily baptized persons, then the ARIS figures represent significant levels of rejection of the baptismal decision by persons once Mormon. To be specific, the level of “apostacy” suggested by the ARIS is 40% in 1990, 48% in 2001 and 47% in 2008.

For persons seeking to convert Mormons to traditional forms of Christianity, the question is: How can the leavers be identified? These are persons who are clearly seeking something promised but not found (by them) in the LDS church.

For political planners, the question is the actual electoral strength of the LDS church in the USA. The LDS church has intentionally sought to strengthen its political influence in Washington, DC, since 1903. This is probably a rational response to the experience of the LDS church in the 19th century when the Federal government’s active program to prohibit the Mormon practice of polygamy led to the imprisonment of many Mormon leaders and ultimately to the disestablishment of the LDS church by Congress in 1887. Today, the claims of the LDS church must be evaluated in light of the fact that almost one out of every two persons claimed by the LDS church as a Mormon does not in fact claim to be Mormon.

Finally, persons leaving the Mormon church should consider obtaining a formal letter of removal from the church so that they will no longer be counted as a member by the church. Common wisdom is that the LDS church will not make this easy and that persistence and diligence is required to bring the process to a successful completion.

---

Footnotes:

1. Barry A. Kosmin and Ariela Keysar, American Religious Identification Survey (ARIS 2008), p. 2, posted at: http://commons.trincoll.edu/aris/files/2011/08/ARIS_Report_2008.pdf (viewed 1 October 2011). Hereafter “ARIS 2008.” ↩︎
2. ARIS figures are from ARIS 2008, p. 5 (Table 3); the LDS figures for year-end 1989, 2000 and 2008 are from Association of Religious Data Archives (the “ARDA”), Church of Jesus Christ of Latter-day Saints, posted at: http://www.thearda.com/Denoms/D_1117.asp (viewed 1 October 2011). [Updated URL for ARDA (as of 5 July 2025): https://www.thearda.com/us-religion/group-profiles/groups?D=211] The official December 31, 1989 and January 1, 2009 membership numbers were confirmed by the LDS Church History Library. Email to author, 26 July & 6 September 2011 (originals in possession of author). The official December31, 2000 membership number is confirmed in Deseret News, 2003 Church Almanac, p. 623. ↩︎
3. Official USA membership statistics from 1950 to 1980 were taken from Deseret News, 1983 Church Almanac, p. 272; Sources for official USA membership statistics from 1980 are provided in footnote 2 above. ↩︎
4. ARIS 2008, p. 5. ↩︎
5. US Census Bureau, 2010 Census Data and Apportionsment Data, posted at: http://2010.census. gov/2010census/data/ (viewed 1 October 2011) (interactive maps provide Utah current and USA and Utah historical information); U. S. Bureau of Census, Eighteenth Decennial Census of Population: 1960, p. x (Table A) (1950 USA population) & p. 46-8 (Tables 1 & 2) (1950 Utah population). ↩︎
6. Deseret News, 1983 Church Almanac, p. 272. ↩︎
7. Ibid. ↩︎
8. Deseret News, 2003 Church Almanac, p. 623 (percentage obtained by dividing the Utah total by the USA total). ↩︎
9. R. Lanier Britsch, Unto the Islands of the Sea: A History of the Latter-day Saints in the Pacific (Salt Lake City: Deseret Book, 1986), pp. 50 – 51. ↩︎
10. D. Michael Quinn, “I-Thou vs. I-It Conversions: The Mormon ‘Baseball Baptism’ Era,” Sunstone Magazine (December 1993), pp. 30 – 44, posted at: https://www.sunstonemagazine.com/wp-content/uploads/sbi/articles/093-30-44.pdf (viewed 1 October 2011). ↩︎
11. The number of stakes in Chile is from Deseret News, 2003 Church Almanac, p. 621 (December 31, 2000 figure); “Statistics Chile,” LDS Church Temples, posted at: http://www.ldschurchtemples.com/statistics/units/world/country.php?country=Chile (viewed 1 October 2011) (74 is the 2011 figure); and Peggy Fletcher Stack, “Building Faith: The LDS Church in Chile,” The Salt Lake Tribune, 1 April 2006, posted at: https://archive.sltrib.com/article.php?id=3661419&itype=NGPSID (viewed 1 October 2011) (74 is the 2006 figure). The Chilean census information is from Republic of Chile, Instituto Nacional de Estadísticas, Censo 2002 Síntesis de Resultados, p. 26, posted at: http://www.ine.cl/cd2002/sintesiscensal.pdf (viewed 1 October 2011) (hereinafter “2002 Census”) [Updated URL as of 5 July 2025: https://www.ine.gob.cl/docs/default-source/censo-de-poblacion-y-vivienda/publicaciones-y-anuarios/2002/sintesiscensal-2002.pdf]. The official Chile membership statistic is from Deseret News, 2003 Church Almanac, p. 621. Sometimes a point is made that the 2002 Census only measured the faith of persons 15 years of age and older. According to the 2002 Census, 25.7 percent of the population is under the age of 15. (2002 Census, p. 12.) If the census figure is increased by this percentage, the number only becomes 130, 395, a little more than a quarter of the official membership number. ↩︎
12. “Country Profile: Chile,” Newsroom, The Church of Jesus Christ of Latter-day Saints, posted at: http://newsroom.lds.org/country/chile (viewed 1 October 2011). [Updated URL: https://newsroom.churchofjesuschrist.org/country/chile] ↩︎

---

---