99.9% of humans will be in hell.
Sahih al-Bukhari 4.567
The world population has been growing exponentially, let's just
say that today's population is about 1/5 of all people who ever lived
(1/2 or 1/3 would probably be more realistic).
Thus, out of thirty billion people, only 30 million make it to
paradise, that is about 2.5% of all Muslims living today!
If we consider this percentage in terms of today's population only,
and assuming that only Muslims will make it, then we are looking
at a maximum of 6 million Muslims entering paradise as opposed
to 1.2 billion Muslims living worldwide!
Or expressed differently, something Muslims do not tell in their
DA'WAH:
everyone converting to Islam today has a chance of about 1 / 200
to go to paradise. And as the percentage of Muslims in the total
world population rises, the probability for each individual Muslim
to make it to paradise is diminishing even further.