Year % 1997 9.52380952380952 1999 4.76190476190476 2000 4.76190476190476 2002 22.7272727272727 2003 22.7272727272727 2004 22.7272727272727 2005 18.1818181818182 2006 18.1818181818182 2007 18.1818181818182 2008 18.1818181818182 2009 21.7391304347826 2010 14.2857142857143 2011 17.3913043478261 2012 17.3913043478261 2013 13.0434782608696 2014 13.0434782608696 2015 13.0434782608696 2016 13.0434782608696 2017 13.0434782608696 2018 13.0434782608696 2019 13.0434782608696 2020 18.1818181818182 2021 18.1818181818182 2022 18.1818181818182 2023 18.1818181818182