Complex sentence: Before November 2001 "The World Factbook" website was updated yearly; from 2004 to 2010 it was updated every two weeks; since 2010 it has been updated weekly.
Split into simpler sentences: Before November 2001, "The World Factbook" website was updated yearly. Between 2004 and 2010, the "Factbook" website was updated every two weeks; since 2010, the website is updated weekly.