Year % 1997 7.57575757575758 1998 7.57575757575758 1999 7.57575757575758 2000 5.71428571428571 2001 5.71428571428571 2002 5.71428571428571 2003 5.71428571428571 2004 5.71428571428571 2005 17.1428571428571 2006 17.1428571428571 2007 17.1428571428571 2008 17.1428571428571 2009 17.1428571428571 2010 18.8405797101449 2011 18.8405797101449 2012 18.8405797101449 2013 18.8405797101449 2014 18.8405797101449 2015 11.5942028985507 2016 11.5942028985507 2017 11.5942028985507 2018 11.5942028985507 2019 20 2020 20 2021 20 2022 20 2023 20