If we assume that only 5% of all the humans that will ever be born have already been born (about 60 billion), then we can predict that 1.2 trillion humans will ever be born. Assuming that the world population stabilizes at 10 billion at a life expectancy of 80 years, it can be estimated that the remaining 1.14 trillion humans that will ever be born will be born in 9120 years. This is the Doomsday Argument.