Year % 1997 6.31578947368421 1998 6.31578947368421 1999 3.05343511450382 2000 3.05343511450382 2001 3.05343511450382 2002 3.05343511450382 2003 4.58015267175572 2004 5.34351145038168 2005 5.34351145038168 2006 5.34351145038168 2007 9.16030534351145 2008 8.3969465648855 2009 9.16030534351145 2010 9.16030534351145 2011 8.3969465648855 2012 10.6870229007634 2013 10.6870229007634 2014 10.6870229007634 2015 10.6870229007634 2016 10.6870229007634 2017 18.0952380952381 2018 18.0952380952381 2019 23.4848484848485 2020 23.4848484848485 2021 33.6448598130841 2022 35.5140186915888 2023 35.5140186915888