Nine Population Strategies to Stop Short of 9 Billion

Abstract

The demographers who calculate the future size of world population are not so much wrong as misunderstood. Humanity may indeed grow to 9 billion people by the middle of this century from 7 billion today and then stop increasing sometime in the twenty-second century around 10 billion. But this outcome is far from inevitable. It is neither an estimate nor a prediction but merely a projection—a conditional forecast of what will come about if current assumptions about declining human fertility and mortality prove true.¹