Wednesday, April 17, 2013

LDS church growth

Back in 2000, my seminary teacher quoted to my class the Rodney Stark projections for church growth, estimating that there would be 64 to 267 million members by 2080. Other researchers have predicted much lower numbers, around only 30 million.

Another sky-high projection was made by a Mormon recently, projecting that there could be 2.6 billion members by 2120. I'd like to consider whether those projections are realistic, but first let's distinguish between growth of the reported membership, and growth of either self-identified or active members.

The official reported church membership is much higher than the number of self-identified Mormons. I’ll just give a few examples:

Members claimed by church in Mexico, 1999 846,931
Self-identified members from census in Mexico, 2000 205,299
Members claimed by church in Chile, 2001 520,202
Self-identified members from census in Chile, 2002 103,735
Members claimed by church in US, 1990 4,175,000
Members projected by ARIS survey, 1990 2,487,000
Members claimed by church in US, 2008 5,974,041
Members projected by ARIS survey, 2008 3,158,000

Sources: here and here. Based on worldwide data, this researcher concludes "approximately 40% of individuals claimed as members by the LDS Church worldwide identify the Church as their faith of preference."

The comparison between the ARIS survey projections and the official membership is interesting because the growth rate implied by the official membership numbers from 1990-2008 is an impressive 30% (~1.47%/year, or 15.7%/decade). The ARIS projections only indicate growth of 16% (~0.83%/year, or 8.6%/decade), which is about the same as US population growth.

So if the church is overstating both total numbers and its growth rate, how can the true worldwide growth rate be estimated? Many observers think that the active members per congregation (meaning wards and branches) has been fairly consistent, so the true growth rate might be close to the growth rate of congregations.

This chart doesn't include the most recent data points, and unfortunately it's not my chart so I can't update it, so I'll list the most recent data for increase in congregations in this table:

Year:Total congregationsIncreaseIncrease as %

As a comparison, the US population growth rate is ~0.9%/year, and world population growth rate is ~1.15%/year. I do expect to see a temporary increase from the change in missionary age over the next 2-3 years, and possibly a slight long-term increase as well. Based on this data, I'll make a few conclusions:
  • The church's growth rate is similar to background population growth.
  • The conclusions drawn by David Stewart, based on a lot of data, are bit out of date but are probably still accurate.
  • Because the church has a higher fertility rate than average, achieving only population growth means they are actually losing members on the conversion side, in spite of an aggressive proselytizing program.
  • The church cannot sustain long-term exponential growth.
  • Therefore, I think the long-term Loomis and Anderson projections are much more believable than the sky-high Stark or Koltko-Rivera projections.