1600 - 1699: 2<p>1700 - 1799: 18<p>1800 - 1899: 79<p>1900 - 1999: 58<p>Still, given the population explosion, it's unlikely that there were fewer autodidacts in the 20th century than in the 19th.<p>Raw data: <a href="http://pastie.org/783067" rel="nofollow">http://pastie.org/783067</a>