English - 1 billion over estimated?
http://esl.about.com/od/englishlearningresources/f/f_eslmarket.htm
French 200 million
http://www.stgeorges.co.uk/foreign-languages/french-courses/
Russian - 20 million
http://www.tlfq.ulaval.ca/axl/francophonie/francophonie.htm
German - 14.45 million
http://www.auswaertiges-amt.de/diplo/en/Aussenpolitik/KulturDialog/Sprache/DeutscheSprache.html
Spanish - 14 million
http://vivirlatino.com/2007/04/27/spanish-second-most-studied-language-worldwide.php
http://esl.about.com/od/englishlearningresources/f/f_eslmarket.htm
French 200 million
http://www.stgeorges.co.uk/foreign-languages/french-courses/
Russian - 20 million
http://www.tlfq.ulaval.ca/axl/francophonie/francophonie.htm
German - 14.45 million
http://www.auswaertiges-amt.de/diplo/en/Aussenpolitik/KulturDialog/Sprache/DeutscheSprache.html
Spanish - 14 million
http://vivirlatino.com/2007/04/27/spanish-second-most-studied-language-worldwide.php