Year Number 2000 42.5531921386719 2002 37.037036895752 2003 15.3439149856567 2004 26.6009845733643 2005 18.0487804412842 2006 19.5121955871582 2007 12.1359224319458 2008 17.9611644744873 2009 20.0956935882568 2010 20.9523811340332 2011 19.9052124023438 2012 18.4834117889404 2013 17.5355453491211 2014 24.0384616851807 2015 21.9047622680664 2016 26.6666660308838 2017 21.4285717010498 2018 22.8571434020996 2019 22.8571434020996 2020 24.761905670166 2021 29.5238094329834 2022 33.9622650146484