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4. The National Federation of State High School Associations. 2014–2015 High school athletics participation survey. 2015. http://www.nfhs.org/ParticipationStatistics/PDF/2014-15_Participation_Survey_Results.pdf . Accessed 27 Aug 2015.
5. The National Federation of State High School Associations. 2009–2010 High school athletics survey. 2010. http://www.nfhs.org/ParticipationStatistics/PDF/2009-10%20Participation%20Survey.pdf . Accessed 27 Aug 2015.