Year % 1997 7.185628742514969 1998 7.701215981470758 2000 8.622652248150258 2001 10.761789600967349 2002 12.835434852893625 2003 10.64257028112449 2004 12.420946116873255 2005 12.347218757794971 2006 12.793373216751041 2007 14.812286689419807 2008 15.103189493433396 2009 15.819337267362688 2010 15.881955395359306 2011 16.884580703336336 2012 18.23204419889503 2013 18.42920353982301 2014 18.869603916332895 2015 18.88641425389755 2016 19.24191750278707 2017 21.138952164009115 2018 21.451104100946374 2019 23.191345503718736 2020 24.3566591422122 2021 25.00567794685442 2022 25.005735260380828 2023 25.06288589069289