Christo notices that I suck at math. Or at least, the statistics I was given—and the charts I put up—might be a little misleading. What you might infer, looking at those charts alone, is that Christianity in the West is declining rapidly, losing adherents, while in Asia and Africa and Latin America Christianity are gaining lots of converts. What I forgot to do was control for population growth. Once you do that, and work the numbers to show Christian growth relative to the growth of the total population, the trend looks a little bit different:
A lower number on the y-axis indicates less percent of the world’s Christian population (data from the pie charts in this earlier post) relative to the percent of the total world population (according to Wikipedia). Thus, although Asia will have a significant amount of the world’s Christians by 2050, its massive population keep the line pretty low.
(If you want to know my calculations, all I did was divide a given continent’s percentage of the world’s Christian population by its percentage of the world’s total population. That’s what the numbers on the y-axis indicate. Since I’m playing with percents and not raw numbers, the actual numbers on the y-axis don’t really mean much, but the graph should do a pretty good job of controlling for shifting population trends in all of this mess—I think. Hopefully.)
What this graph shows (assuming I did my math right) is that once you control for total population European Christianity’s ‘decline’ isn’t really as drastic as the previous charts had made it appear—though there does seem to be some decline in terms of raw numbers as well, though that isn’t clearly demonstrated by this chart. What this chart does show is that the number of Christians in Africa, even once you control for population growth, has absolutely exploded. Asia’s is growing too, though perhaps not as much. And Europe, North America and Oceania are slightly, though not dramatically, in decline.
By the way, if anyone can spot some mistakes in my logic, I’d appreciate it. I’d like to provide graphs and charts that actually, you know, reflect reality.
First, if Christians had looked at this chart in 1900 I think they would have balked at the figures for Africa. No one would be expecting that kind of growth, but it happened anyway. Will a similar thing happen in Asia this century? Underground Christianity in China has been taking off for some time now—what will those figures look like in 50 years?
Second, it’s important to remember that these charts and graphs and whatnot can only give us numbers, not a picture of how devout or orthodox or vibrant the Christianity in any given region is. Some of the recent expansion in the global south owes much to Pentecostal/charismatic revival movements, but it remains to be seen whether the Christianity that has taken root in this kind of movement is sustainable enough to last fifty years. So some of this is kind of up for grabs.
But it is compelling data, isn’t it?
(Update: Now, what I’d really like is some raw numbers to work with. If I could get my hands on the total Christian populations residing on each continent in 1900 and 2008, and a projection for 2050, I could start to understand this stuff a lot better. So, if anyone knows where to find that information, I’d be much obliged . . . )