Year Number 1996 9.67741966247559 1998 7.48663091659546 2000 8.51063823699951 2002 7.93650770187378 2003 5.29100513458252 2004 5.9113302230835 2005 6.34146356582642 2006 7.80487823486328 2007 5.33980560302734 2008 4.36893224716187 2009 2.87081336975098 2010 3.80952382087708 2011 3.3175356388092 2012 4.7393364906311 2013 4.7393364906311 2014 3.8461537361145 2015 4.2857141494751 2016 4.7619047164917 2017 5.7142858505249 2018 10.9523811340332 2019 13.8095235824585 2020 18.5714282989502 2021 29.0476188659668 2022 30.6603775024414