Making Growth Projections using AAGR

A researcher may be called upon to either evaluate whether the team’s objectives or the proposed faith-based goals of church leaders are realistic and attainable. Or perhaps the researcher will be asked to suggest realistic growth goals and objectives. These goals could pertain to both the growth of the number of Christians and the growth of the number of Churches. Two approaches to setting and evaluating growth goals based on Average Annual Growth Rates (AAGR) are presented here. Also three perspectives on actual AAGRs are presented.

1. Make Growth Projections using AAGR and The Law of 72.

It is relatively simple to make growth projections based on Average Annual Growth Rates by using the Law of 72.
The Law of 72 states that the number 72 divided by the Average Annual Growth Rate equals the number of years for the beginning quantity to double.

Let’s look at several examples

  • Area X has a church planting average annual growth rate of rate of 1%. It will take 72 years for the number of churches to double at this rate. (72/1=72)
  • Area Y has a church planting AAGR of 3%. There it will take 24 years for the number of churches to double.(72/3=24)
  • Area Z has a church planting AAGR of 10%. Thus the number of churches will double in 7.2 years. (72/10=7.2)

2. Determine the number of years to achieve a growth goal using AAGR

Determining the number of years to achieve a specific growth goal using AAGR is more difficult. It is easiest to use a spread sheet. In the Tools section of Resource Downloads, there is an Excel spreadsheet provided for this purpose: “The Church Growth Calculator.” This spread sheet permits you to enter values for (1) the desired growth rate, (2) the year to start and (3) the church count at the start year. Experimenting with different values will allow you to suggest faith-based goals that are also realistic.

AAGRs from a Harvest Field Perspective

Let us consider the example of the Philippines. When the DAWN goals were sent in 1975, there were approximately 5,000 evangelical churches in the country and the goal established for the year 2000 was 50,000 churches. What Average Annual Growth Rate would be needed to achieve this goal? And is this a realistic growth rate?

I initially tried a 5% AAGR in the spreadsheet. But this yielded a total of 16,933 churches in 25 years. Not enough. Next I entered 10% - and the result was 54,175 Churches - a bit more than the goal.Experimenting with figures showed that an AAGR of 9.65% would result in 50,031 churches in 25 years.

The question now arises, is this a sustainable, realistic goal? In retrospect, we know that indeed this is a sustainable growth rate, because the churches in the Philippines not only met the goal of 50,000 churches by the year 2000, but exceeded it. So a 10% AAGR over a 25 year period is realistic and sustainable growth rate.
This same spreadsheet can also be used to project the number of Christians using Average Annual Growth Rates. Enter the year, the beginning number of Christians and the AAGR.

AAGRs from a Global Perspective

It is enlightening to note that The Center for the Study of Global Christianity, based at Gordon Conwell Seminary, published in June 2013 an excellent report regarding Christianity in its Global Context. This report presents analysis for the period 1970-2020 and points out implications for society, religion and mission. The full report can be found online at www.globalchristianity.org/globalcontext. The report lists AAGRs for the number of Christians for the fifty year period 1970-2020. Nepal leads the list with a 10.93% AAGR. China is second with10.86%. Mongolia and Cambodia are also near the top with 5.96% and 5.87% AAGR respectively. The West African Nations of Benin (4.85), Burkina Faso (4.81%) and South Sudan (4.67%) also have high AAGRs. This gives us an idea of sustainable AAGRs over a longer period of time. Keep in mind that an AAGR above 3. 52 is “Above Average” and only 36 countries out of 235 fall into this category. The global Average Annual Growth Rate is 1.47%, exactly equal to the global population AAGR for the same period.

AAGRs of Church Planting Movements

Likewise we must keep in mind that cases studies of Church Planting Movements are reporting “exponential growth rates”. David Garrison in Church Planting Movements (1999) documents a case of Church Growth with an astounding 184% AAGR in China, a 35% and 40% AAGR in Latin America, a 61% AAGR in India and a 78% AAGR in Cambodia. Breakthroughs, such as these, can result in explosive growth!

Keeping these perspectives in mind will permit you to evaluate objectives and faith-based goals, while keeping in mind that God is a God of surprises!