Year including construction (constant 2015 US$) 1991 8133.097079967052 1992 7303.372007529767 1993 6654.553981836472 1994 6615.289968626217 1995 7771.9052043427755 1996 7667.130303602111 1997 7882.451583266922 1998 8400.415174544676 1999 8454.98669025583 2000 9217.42121901733 2001 10516.885273662807 2002 10156.65451802545 2003 12814.537009388932 2004 12979.297279110055 2005 14260.48352390229 2006 13714.150978136662 2007 14109.221135473352 2008 13035.105160896579 2009 12243.508671795038 2010 11796.775172598376 2011 11453.599834851946 2012 12270.994687267468 2013 12485.551553006646 2014 13600.006376779333 2015 15129.488571877497 2016 16260.234137048983 2017 15707.853134176761 2018 15557.533127169027 2019 14851.754994352976 2020 14979.544216903645 2021 14185.411074223483 2022 12576.007443573508