Year % 1992 14.15 1997 3.6 2001 31.95 2002 31.61 2003 5.12 2004 4.05 2005 2.9 2006 3.13 2007 3.03 2008 3.02 2009 2.77 2012 2.54 2013 2.38 2014 2.36 2015 2.2 2016 1.79 2017 1.92 2018 1.92 2019 1.74 2020 1.74 2021 2.07