Eclectic Christian

I have stumbled upon a very interesting ratio that can be used as a predictor for church growth or decline. That is, the ratio between attendance and membership. Obviously if a church is growing very rapidly, especially if that growth is from new converts the church will tend to have a much higher attendance to membership ratio. Conversely if a church is in decline, with not a lot of new blood coming in, the ration of attendance to membership would be significantly lower.

To see if this holds true I considered three sets of data: The attendance and membership of mainline churches in Canada, the attendance and membership of Evangelical churches in Canada, and the attendance and membership of major denominations in the United States.

My first two set of data come from Bruce Guenther by way of Canadian Christianity. Guenther is associate professor of church history and Mennonite studies at Associated Canadian Theological Seminaries and has compiled statistics on over 160 denominations.

In 1981 the Canadian Mainline churches had 2,240,991 members and attendance of 965,534, a ratio of attendance to members of 43%. In 20 years they dropped to 1,666,715 members and attendance of 723,673 in 2001 a ratio of also 43%. So for Mainline churches, an attendance to membership ratio of 43% corresponded to drop in attendance of 25% and a drop in membership of 26%. The average drop per year was roughly 1.25%.

The converse situation has happened with the Evangelical churches in Canada. In 1981 they had
974,295 members and attendance of 758,383, a ratio of attendance to members of 78%. In 2001 they had 1,341,897 members and attendance of 1,130,237. This was a ratio of 84%. The starting attendance to membership ratio of 78% has translated into a growth of 38% in members and a 49% growth in attendance. This translates into an average growth per year between 1.9% and 2.45% depending on the measurement.

I found data on a range of larger denominations here. The author drew the same conclusions that I had drawn about the relationship between growth and attendance.

I plotted the data as shown below and added a best fit line (shown in red).

So what does this show us?

It shows us that generally if your attendance is under 50% of your members and adherents your church will likely decline over the next ten years. Conversely if your attendance is greater that 50% of your members and adherents, your church will likely grow over the next 10 years. There are of course exceptions to the rule.

So let us get back to our original topic, the Southern Baptists. For the Southern Baptists, attendance as a percentage of membership is 37%. But, because this graph shows attendance as a percentage of membership and adherents, the Southern Baptist ratio is currently at 27%.

This means that the Southern Baptist are at great risk of decline over the next ten years. In fact they were one of only two large denomination that grew during the 1990s despite having a ratio of under 40%. We know from the data already coming in that the subsequent data won’t be as kind.

But there is a little twist to the numbers here. There is a positive “Evangelical” factor that I have not yet been able to quantify. That is the more conservative and evangelical a church, the more likely that they will experience growth despite the percentage ratio. This is likely what allowed the Southern Baptists to grow in the 1990s despite their very low percentage ratio.

Therefore, I would argue, contrary to some commentators, that the Southern Baptist move to the right over the last 20 years had not precipitated its decline, but probably prevented further decline. Perhaps this has given the denomination a bit of a reprieve and a chance to get its house in order. We shall see what the next twenty years brings.

This entry was posted on Thursday, June 26th, 2008 at 2:49 pm and is filed under church growth. You can follow any responses to this entry through the RSS 2.0 feed. You can leave a response, or trackback from your own site.