All-time historical world population?

Question

There are currently about 6.5 billion people on the Earth (source: CIA statistics). Are there any good educated guesses as to the all time human population for all generations that ever lived on Earth? (Yes, I know this would be a very rough guess, but I would still like to hear an estimate from a credible source.)

The reason I am curious is we obviously live in a very unique time with technological advancement being what it is. So I was just curious as to what the statistical odds of me being born in this very unique time. (math: current population / all time poulation)

Answer 1

The top demographers in their field, who have gone back 100,000 years (Homo Sapiens are at least 190,000 years old), have come up with the figure of 120 billion, which I believe is a conservative estimate...

Roughly 5% of all humans ever born, are alive today!

Answer 2

My prediction would be about 12 billion to 15 billion people.