Market Liquidity
Why Are There So Few Republican Scientists?


Gertrude Himmelfarb once wrote dismissively of historians who believed that menarche was more important than monarchy. Ridiculous, she claimed.

She was wrong. Here we have Courtney Knapp with an extraordinary number calculated by Brown's excellent David Weil:

Menarche: Better health is causal factor behind the biological capability to become pregnant. Quick refresher course for those who slept through biology.... [H]ealthier girls have their first period at a younger age, and worldwide we have seen a decline in the age of menarche accompanying improved nutrition and sanitation. According to David Weil, in South Korea, the average age dropped from 16.8 to 12.7 between 1958 and 1998...