Long Term Decline Results of the General Limited Enthusiasm Model (Births, Deaths, Reversion)
Principles Established Extinction Threshold Percentage of Enthusiasts Low Reproduction Potential    Applications Church of England   Details of Models Limited Enthusiasm  Births, Deaths & Reversion  Renewal   Details of Results Summary of Results Short Term Revival  Long Term Growth Long Term Decline Growth via Renewal   References & Bibliography  Mathematics of Church Growth Church Growth Revival  System Dynamics  Sociology of Religion Epidemics  Social Diffusion Publications Articles Models for Download	Long term decline in the General Limited Enthusiasm Model is typical of the church attendance and membership patterns seen in the older denominations particularly, Methodist, Anglican and United Reformed Principles Established Extinction Threshold The model has two thresholds the revival growth threshold - over which rapid growth occurs, and the extinction threshold. The extinction threshold is always below the revival-growth threshold. Both are determined by the loss rates and the duration of the enthusiastic period. The revival-growth threshold is discussed on the long-term growth page. If the reproduction potential is under the extinction threshold the enthusiasts are not reproducing themselves fast enough to survive. The number of enthusiasts keeps declining, curve 2, figure 1. Thus the church ends up declining to extinction at a speed proportional to its losses, curve 1, figure 2. Figure 1 The extinction threshold is line 3 in figure 2. Unlike the revival-growth threshold, the extinction threshold does not drop as the proportion of unconverted people rises. Thus the church has no chance of recovery. Ultimately it will become extinct. Extinction occurs when the revival threshold equals the extinction threshold, as indicated by the arrow Figure 2 Equilibrium at a non-zero value of church numbers can only occur when the reproduction potential equals the revival threshold. In the above case this cannot happen as the church becomes extinct before that can happen. Line 3 is above line 2 in figure 2. Not all decline leads to extinction. If the reproduction potential is above the extinction threshold then the church numbers will stabilise at some non-zero value. Thus decline doesn't necessarily mean extinction. Return to Top Percentage of Enthusiasts Rising During Decline One unusual effect of decline in church numbers, especially if the church is heading for extinction, is that the percentage of enthusiasts can rise. The actual number are falling - enthusiasts are not reproducing themselves fast enough. However the church overall is declining even faster, thus the fraction of the church that is enthusiastic becomes greater. See figure 3. Figure 3 Thus as the church declines and individual congregations get smaller they may appear more enthusiastic, even more committed. However unless the enthusiasts reproduce themselves faster then the appearance of enthusiasm is misleading. The church is still becoming extinct.   Return to Top Low Reproduction Potential A church with a low reproduction potential (well under the extinction threshold) can survive if it has no adult or child losses. The church survives on biological growth alone. However it is then very sensitive to losses. Consider an extreme case of a church with no enthusiasts. accounting for 20% of the community, and with no adult reversion. With no child losses the church stays at 20% (line 1 figure 4). If 25% of the children of believers are lost from the church then the decline sets in (curve 2, figure 4). The church will eventually become extinct, but it takes a very long time to do so. It has halved in 200 years. It is not losing 25% of its people, but only its children. The 75% retained go on to have children of their own thus decline is slower than one might imagine at a first glance.     Figure 4 A church with a 50% child loss is halved in about 100 years. If all the children are lost the church is extinct in 70 years. Just because a church is declining slowly does not mean it does not have a crisis. Maybe it has small losses and no enthusiasts. The only measure of a church's health (from the point of view of growth) is the level of enthusiasm of the enthusiasts. Is there enough reproduction potential for them to increase the number of enthusiasts? A church with child losses may decline so slowly that people may not think there is a serious problem. Even in curve 3 in figure 4 after 200 years the church survives, buildings are maintained, salaries and pensions are paid, albeit on a declining scale. Nevertheless the church is lifeless (no enthusiasts) and heading for extinction. Return to Top Applications Church of England The Church of England is in decline. Based on church attendance surveys its attendance has fallen from 1.7 million in 1979, through 1.3 million in 1989 to 980,000 in in 1998. Fitting this to the general limited enthusiasm model gives a reproduction potential of 1.08, under the extinction threshold of 1.11. Thus the church is heading for extinction but over a very long time scale. Extrapolating the model into the 21st century show the attendance down to half a million by 2022, and a mere 80,00 by 2100 (figure 5). If this forecast is correct the church will be a very different institution by the end of the century with many parishes completely closed. Figure 5 Remarkably the attendance of the church will be less than that of the new churches by 2025 as they are undergoing revival growth. As there are similar growing congregations in the church of England the above forecast maybe pessimistic as the evangelical and charismatic revival could become the dominant force in the Church of England. However there is no reliable data to determine these effects numerically. As noted above the reproduction potential is not far below the extinction threshold. A number of scenarios can be given that would see the decline slowed or reversed (figure 6). Figure 6 Curve 1 is the extrapolation based on current figures. Curve 2 shows the effect of keeping all the children in church. The church avoids extinction but the decline is very similar. Curve 3 shows the effect of halving the adult reversion. As tragic as the loss of children, usually teenage, is they can get converted later in life. the main losses are among adults. Curve 4 is with the child loss stemmed and the adult losses halved. This time stemming child loss has more effect, as it is not swamped by adult losses. Curve 5 is with no child losses and the adult reversion a quarter of its current rate. This is enough to tip the church into revival growth. Of course an increase in enthusiasm, reproduction potential would have far more effect. However it does show what could be achieved if losses were stemmed. Return to Top