Here's part of an interesting article (from http://www.religiondispatches.org/ar...not_adding_up/) which destroys the Mormon claim that the cult has 13,000,000 or more members.
"But new data suggests that Mormonism may no longer be (as it is often described) among the fastest-growing faiths in the United States. Instead, American Mormons appear to be settling into the twenty-first century as a maturing minority having an increasingly hard time holding onto younger members.
Official LDS Church statistics for 2011 count 6,144,582 Mormons in the United States in 2011, comprising about 2% of the nation’s population. Church statistics also show a 30% membership increase between 1990 and 2008—a rate double general US population growth.
But recent studies tell a different story—different because whereas LDS Church records count anyone who has ever been baptized, demographers and pollsters count only those who currently identify themselves as Mormon. Those are the parameters for the landmark Trinity College American Religious Identification Survey: a two-decade project that has produced the largest and most accurate database of self-reported religious identification ever compiled, with 100,000 randomly sampled participants. According to Rick Phillips and Ryan Cragun, the authors of a study of Mormons based on ARIS data, self-identified adult Mormons make up not 2% but rather 1.4% of the adult US population—that’s about 4.4 million LDS adults."
and
"In fact, additional studies by Cragun and Phillips show that retention rates of young people (young men especially) raised Mormon have dropped substantially in the last decade: from 92.6% in the 1970s–2000s to 64.4% from 2000–2010. Rising rates of disaffiliation go a long way towards explaining the gap between LDS Church records and the ARIS population estimates."
And here is a quote from a the Mormon Social Science ***ociation:
“. . .regarding retention rates… the LDS Church does not release this information. But there are ways to estimate this and several researchers have done so, giving us our current best estimates. For instance, Rick Phillips (2006), using census data for a variety of countries, compared the membership information supplied by the LDS Church in its annual almanac to the self-reported membership identifications of people in those countries and found that the LDS Church over-estimated its membership. The actual number of Mormons in those countries ranged from 20% to 70% of what the LDS Church claimed. The major implication of this finding is that retention rates of Mormon converts are fairly low.”
How do Mormon figures compare with Jehovah's Witnesses? The Witnesses, who only count active "publishers," those who actively distribute Jehovah's Witness literature and are involved in the cult, as having an active membership of 7,782,346. So, one might say the Witnesses have around 3,000,000 more active members than the Mormon cult. (see Wikipedia stats)
The Witnesses do not count those who are not actively participating in their cult, or "ghost" members, or the total number of those baptized, as do the Mormons. The Mormons cover up their lack of success in growth by counting people who may not have sat in a Mormon chapel in twenty years - just so they have been baptized and have not formally resigned, they are counted. I believe ghost members are counted until age 100, even though they never attend services. This reminds me of the Roman Catholic practice of counting ALL baptized individuals, even thought they may not have darkened the door of a Catholic Church in fifty years. Even if these former Catholics spend every Sunday in a Calvary Chapel, they are still counted as Romans.
So folks, the Mormon cult is deceptive and super-inflates its numbers to give the impression that it is growing, when in fact, the cult is in decline! It is losing converts in droves because the missionaries are dishonest - they are head hunters, want to get prospects baptized and into the cult a.s.a.p. so that their "mission" is successful. Doctrine is secondary, and many converts are disgusted when they find out the truth about Mormon beliefs and the sordid sexual history of Joseph Smith, which is all over the Internet.
So, Mormon claims to 13 million members is bogus. The cult is losing members, and the ward door are revolving doors!