About a quarter of the world’s population, or 1.6 billion people, are Muslims, with the US home to over three million. Countries with the most Muslims are Indonesia with 207 million, Pakistan with 159 million, India with 151 million, and Bangladesh with 132 million.
Countries seem either to have a lot of Muslims or very few Muslims. For example, of the sixty countries with the highest Muslim populations, only 14 had Muslim population percentages between 20% and 80%. If Muslims were randomly distributed we would expect to see at least 40 of these countries having those Muslim population percentages, not 14.
What the data says is that if you were to draw a graph of Muslim population percentages, it would look like the letter “U” - an inverted normal curve. The conclusion is that it is statistically significant that Muslims either make up over 80% or under 20% of the population most of the time.
Another indication of the inverted “U” is that only 8 countries fall within plus or minus 10% of the mean.
Christianity’s distribution is similar but flatter: 13 countries fall within plus or minus 10% of the mean.
So what does this mean? Birds of a feather flock together? Sometimes it’s good to get out, see the world, see how the other half lives. Maybe the world might be better off if there was a little percentage flattening.