November 24, 2010 - Since 2004, The World Factbook website has been updated on a bi-weekly schedule. Culminating a three-month trial effort, we are pleased to announce that the Factbook will now be updated on a weekly basis.
World Factbook Updates - November 24, 2010 (https://www.cia.gov/library/world-factbook-updates-november-24-2010.html)