Year Number 1996 17.021276473999 1998 3.72340416908264 2000 7.93650770187378 2002 29.100528717041 2003 28.1407032012939 2004 28.6407775878906 2005 24.7572822570801 2006 28.5024147033691 2007 26.0869560241699 2008 27.4038467407227 2009 29.3838863372803 2010 31.2796211242676 2011 36.9668235778809 2012 38.8625602722168 2013 43.1279602050781 2014 53.3333320617676 2015 55.238094329834 2016 50.476188659668 2017 50.476188659668 2018 46.698112487793 2019 44.3396224975586 2020 41.9811325073242 2021 45.2830200195313 2022 40.0943412780762