Year % 1989 6.077283 1993 5.120059 1995 8.645152 1996 8.776123 1997 6.720176 1998 6.405578 1999 5.74298 2000 5.836459 2001 5.815494 2002 5.729944 2003 15.95368 2004 5.85608 2005 5.888726 2006 5.862156 2007 5.779496 2008 5.939939 2009 5.56413 2010 5.726254 2011 5.710382 2012 5.676914 2013 5.401003 2014 5.514231 2015 5.470802 2016 5.651514 2017 5.337267 2018 5.450391 2019 5.658461 2020 5.289817 2021 5.421543