If people are leaving the mega-cult in droves, it seems unlikely there are as many active members as claimed.

FWIW, Marlin Jensen, church historian said last year that he thinks there about 5 million.

Use the search function on this site and you can find reams of analysis on this topic if you care about the reasoning behind it. Estimates run in the range of 4-6 million active members, even analysis from TBMs hit that range.

3-5M is the range of estimates I've seen.

Outside the US, national censuses indicate that about 1/10 to 1/2 of the people LDS have on their books actually claim to be LDS. The Trib has run a few articles on these; one is linked below:

http://www.sltrib.com/sltrib/blogsfaithblog/54497395-180/church-census-lds-reported.html.csp

If you extrapolate the 220,000 people who actual marked "Mormon" on their census forms to the 1.1M the church claims is there, you end up with about a 20% reality:church-claims ratio. Apply that worldwide outside North America, and you end up with only about 1.5M active LDS outside the US.

Yes, 4 to 6 million seems to be the best guess. The number has probably already peaked, and will continue to decline.

Something which would be more interesting to look at would be the real value of tithing. My bet is that tithing revenue will decline (in constant dollars, to account for inflation) faster than membership.

As the number in Europe is already decreasing, as well as the States outside of Utah and the Moridor, and with lower numbers of active members everywhere else in the world except for Africa and perhaps the Philippines, and as converts tend to have lower income than the established members leaving, tithing will decrease. There will also be a greater number of members switching to paying on net income as well as not paying a full 10%.

Actually there are probably more EX-Mormons than Mormons:

"FAQ: How many exmormons are there?" http://packham.n4m.org/morexmos.htm

http://exmormon.org/phorum/read.php?2,803893,803922#msg-803922

But just how many Mormons are there? How many are active in the church? According to a 2008 study, 1.4% of the U.S. population self identifies as Mormon:
(http://commons.trincoll.edu/aris/files/2011/12/Mormons2008.pdf)

According to Wikipedia, approximately 2/3 of Mormons in the US are inactive (http://en.wikipedia.org/wiki/Less-active_Mormon) so this would mean that only about a third are active in the church. Using the LDS fourteen million member figure this would mean that only about four and a half millions of Mormons are actually active members.

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