Application of the Limited Enthusiasm Model with Reversion, Written in 2022.

The Church in Wales is an Anglican Church in the principality of Wales. It was originally part of the established Church of England but was disestablished in 1920. Nevertheless, it retains some vestiges of its prior establishment. For example, it requires the UK parliament to change some of its laws, such as marriage.

The Church in Wales contains a mixture of churchmanships, and for many years all were on the conservative side. However, in the last 25 years, it has become increasingly liberal. In common with most historic UK Christian denominations, it has steadily declined since 1960. This analysis investigates the likelihood of decline leading to denominational extinction.


Estimating Model Parameters

I will use the Church in Wales’ membership and attendance data to estimate the parameters of the Limited Enthusiasm Model with Reversion. Using this cut-down version of the Demographics Model avoids estimating values for child retention among church members, hardening rates etc. There is no information about these values for this church. The reversion model has only five parameters:

  1. Reproduction Potential
  2. Duration Enthusiastic
  3. Loss Rate
  4. Fraction of Converts who Become Enthusiasts
  5. Initial Fraction of Enthusiasts in the Church

The key parameter is the reproduction potential. If this potential is less than one, then the decline of the Church in Wales is to extinction.


Calibration Strategy

The best fit between data and model is found using least squares. Avoiding systematic deviations from the data can help reduce the number of best fits. To help find the most suitable parameter values, I vary parameters 3-5 above and optimise for 1-2, the reproduction potential and duration enthusiastic. Out of this optimisation set, I count how many indicate the church will become extinct. Although these parameter values cannot be determined with certainty, the likelihood of extinction is more robust.


Membership 2000-2019

I took the membership data from Church in Wales publications and Brierley (2008-2020).

Virtually every optimisation indicates that the Church in Wales will end up extinct.

A typical optimisation is given in figure 1. The reproduction potential chosen was an average figure of 0.72, well under the extinction threshold of 1. As I have done with other declining churches, I chose the fraction of converts who become enthusiasts as 10%. If I had used 50% for this parameter, the reproduction potential would increase to 0.81. However, there is no evidence for this many converts becoming enthusiasts.

Figure 1: Data Fit for Church in Wales Membership and the Limited Enthusiasm with Reversion Model

Range of Optimised Parameters 2000–2019

The optimisations for 2000–2019 indicate a large range of possible parameter values:

Reproduction Potential0.23–0.92
Duration Enthusiastic1-4 years
Loss Rate
(Reversion and Deaths)
4%–6%
Fraction of Converts who Become Enthusiastsabout 10%
Initial Fraction of Enthusiasts in the Church0.5%–3%
Model Parameters for the Church in Wales

The loss rate is slightly less than the Presbyterians and Independents in Wales. This may result from the Church in Wales’ wider population coverage, giving it some less-aged congregations.

If I had used 50% of the converts enthusiast, then the range for the reproduction potential would be 0.6 to 1.005. However, although the upper value would just avoid extinction, that value is only possible with a very high loss rate masking conversions. In my experience of the church, I have seen no evidence to support this scenario.


Attendance 2000-2018

I also obtained attendance data for the Church Wales, which they published up to 2018. A data fit for an average reproduction potential of 0.6 appears in figure 2. The range for this parameter is 0.2 to 0.91, very similar to the range obtained using membership data. Both attendance and membership indicate the Church in Wales is heading for extinction.

Figure 2: Data Fit for Church in Wales Attendance and the Limited Enthusiasm with Reversion Model

Possible Extinction Date

Although the model forecasts extinction, it does not indicate an extinction date. The model contains exponential decline because it does not capture the effects of ageing. By 2060 it predicts a church with just 3,000 in attendance. This is probably too optimistic.

Fitting a straight line to the membership data gives a more realistic estimate of the extinction date, as decline through ageing is a linear process. The Church in Wales is forecast to be extinct by 2038, figure 3. The same date is obtained using the attendance data. By contrast, the limited enthusiasm model gives 10,000 in attendance in 2038. The church’s attendance in that year will likely lie somewhere between the two figures due to the presence of some strong urban congregations.

Figure 3: Linear fit to the Church in Wales membership data.

The Church in Wales has a similar decline pattern to other historic denominations, such as the Church of Scotland, the United Reformed Church and the Methodist Church.


Long–Term View

The membership of the Church in Wales from 1880 to the present day shows the classic institutional lifecycle, figure 4. The church did well in the latter part of the 19th century and the early 20th century. Disestablishment in 1920 did not hinder its growth. However, it declined from the Second World War onwards. This decline temporarily halted during the 1950s, like many UK denominations.

Figure 4: Membership of the Church in Wales

Personal Reflection

I spent 21 years of my life in two different Church in Wales congregations. So, documenting this decline is far from academic but gives me immense sadness. During that time, I watched the church change from a somewhat stuffy and old-fashioned church into one that appeared more modern and contemporary. However, this transformation has been achieved by a significant liberalising of the church’s beliefs, losing its respect for both the scriptures and the traditions it had received.

Sadly, this liberal transformation of the church is likely to hasten its decline rather than reverse it. Churches do not grow by becoming like society and attracting people, but by becoming like Jesus and converting people. For that to happen, it needs a clear understanding of the gospel of salvation and the power of the Holy Spirit to change people. The church needs to confront the current cultural norms rather than embrace them. I hope and pray that the Church in Wales will turn from its current liberal path and re-embrace the truths of Christianity before it is too late.