Disturbing statistics

Like many, I was struck by this widely reported statistic, from an analysis by Texas State University: congregation growth at evangelical churches increased 50% during each recession between 1968 and 2004.

However, note this commentary:

This has to do with numbers, and how journalists use them.

Let's look at the sentence. Growth RATES increase by 50 percent. It's cited just like that in the Times article. Sounds impressive. Except it's not. Well, not that impressive.

I Googled the actual study, [PDF] which found a correlation between economic downturns and an increase in Evangelical growth. The growth rate increased from .98 percent to 1.52 percent in recession years. Now that lands with a turd-like thud on the page, doesn't it? Citing it as a percent change will sex that right up.

A 1 percent to 1.5 percent increase is indeed a 50 percent rise in the rate. (Ex: If your church has 1000 members, it would grow by about 10 people in a non recession year, or 15 during a recession.)

. . . expressing the change in growth rate as a 50 percent "jump" gives people the impression that Evangelical churches GROW by 50 percent in recessions [which is exactly what I thought when I read it the first time]. At best, it makes the issue unclear. At worst, it distorts the truth.

If you're going to report the percent change, I think you owe your readers the raw numbers, too.