Year Number 1996 61.7021293640137 1998 68.0851058959961 2000 65.0793685913086 2002 65.6084671020508 2003 39.1959800720215 2004 22.8155345916748 2005 21.8446598052979 2006 14.9758453369141 2007 14.4927539825439 2008 12.5 2009 9.95260620117188 2010 9.47867298126221 2011 14.2180099487305 2012 13.2701425552368 2013 9.95260620117188 2014 16.1904754638672 2015 14.7619047164917 2016 14.2857141494751 2017 19.0476188659668 2018 19.3396224975586 2019 27.8301887512207 2020 25.943395614624 2021 25.4716987609863 2022 31.6037731170654