Take a look at it again. They're talking about population growth in a decade, not in a year.
It is by definition impossible to have true compound population growth by year. Children born this year do not have kids of their own next year.
BTW, almost all of the population explosion predictions of the last 40 years have been wildly too high. Population growth rates are falling rapidly almost throughout the world.
No, Muhammad waited until Ayesha was 6 before he married her and 9 before he raped her.