Note the actual number converted was thus 1 per enthusiast, as about 50% of the people they met were already converted. One enthusiast only needed to bring one other person to a meeting where they also became converted and an enthusiast! The figure below show such a simulation where the numbers are measured as a fraction of the total adult population of Wales:
It is not possible to tell how many of the converts also became enthusiasts. If it was only 10% then the conversion potential would have to be much higher, around 18 converts per enthusiast, and the enthusiastic phase longer, about 1 month (see Hayward 2000).
In reality these parameters could vary widely for different enthusiasts, with the model yielding their average value.
Further details of the calculations are given in the explanatory notes including a breakdown of the figures associated with each denomination over the period.
Welsh Revival 1904-5
Application of the Limited Enthusiasm Model
Rapid growth in the churches in Wales occurred during 1904-5 in what is sometimes known as the "Evan Roberts" revival. In 1904 the combined total membership for Welsh churches stood at 48.94% of the total population and rose to 53.43% by the end of 1905. The bulk of the 100,000 converts came in a period of about 12 months (see Hayward 1999) . Simulations show that the reproduction potential for each active believer (enthusiast) was just over 2. If all converts had also become enthusiasts then the potential number converted by each enthusiasts was also 2 with the duration of the enthusiastic phase about 1 week.