"The U.N. recognises that its own figures come with a 1 to 2 percent margin of error. Today's population could actually be 56 million higher or lower than 7 billion," according to U.N. population estimates expert Gerhard Heilig.
"There is a window of uncertainty of at least six months before and six months after the 31 October for the world population to reach 7 billion," he added.
Still, if it hasn't happened yet it looks like it will pretty soon. And as we reported Friday, there's also been work done on who is the world's "most typical person."