Year constant 2015 US$ 1995 1620.0181351303834 1996 1445.4294390981886 1997 1477.121451545357 1998 1235.0580939025187 1999 1226.8251963315793 2000 1207.2121915170055 2001 1268.0808961754776 2002 1689.9833228929626 2003 1562.7653073100464 2004 1911.008752919852 2005 2054.476235506015 2006 2358.740429631038 2007 2934.1479041799084 2008 3072.062373154789 2009 3423.5934400350666 2010 3670.491625701105 2011 3812.1380925417084 2012 4141.718644158095 2013 4343.384887484893 2014 4644.391422756408 2015 4937.413484537659 2016 5257.67843922422 2017 5570.615037177178 2018 5766.4375474184035 2019 5979.680269756801 2020 5930.415118644965 2021 6305.220382774918