1 ...
of the 41 self-made under 40 is a woman, 21-year-old Kylie Jenner, founder of Kylie Cosmetics. She made her debut this year as the youngest self-made billionaire to date. The rest are all men.
14 ...
of the remaining female billionaires under 40 inherited their fortunes.
$2.1bn each ...
the net worth of John Collison, 29, and his brother Patrick, 30, co-founders of payments company Stripe. Jenner replaces John as the youngest self-made billionaire.