Year Percent of GDP (Units) 1995 44.894 1996 43.455 1997 42.444 1998 40.554 1999 40.793 2000 40.141 2001 38.086 2002 37.227 2003 37.259 2004 35.606 2005 36.852 2006 35.242 2007 34.330 2008 34.471 2009 36.258 2010 34.667 2011 37.051 2012 36.757 2013 39.596 2014 40.153 2015 42.898 2016 39.971 2017 38.515 2018 38.659 2019 39.314 2020 39.393 2021 40.170 2022 39.842 2023 41.476 2024 41.005 2025 40.040 2026 39.260 2027 38.946 2028 38.947 2029 38.951