Year % 1997 1 1998 0.9 1999 0.9 2000 1.2 2001 1.1 2002 1.1 2003 1.3 2004 1.3 2005 1.2 2006 1.2 2007 1.2 2008 1.3 2009 1.4 2010 1.5 2011 1.5 2012 1.5 2013 1.6 2014 1.6 2015 1.6 2016 1.6 2017 1.7 2018 1.8 2019 1.9 2020 1.7 2021 2.1 2022 2.1