Year including construction (constant 2010 US$) 1991 39383.2102806696 1992 30326.9718500056 1993 25428.7621004791 1994 20309.8127319428 1995 18393.4639484584 1996 18513.874045786 1997 19550.874262477 1998 19658.807766902 1999 20469.0466708341 2000 23294.9119133678 2001 25970.8336176354 2002 28680.2608203736 2003 29700.8310908396 2004 31881.2482401013 2005 33408.1241220146 2006 36244.9169374352 2007 37229.7872299537 2008 37222.8273434451 2009 37487.9122194735 2010 39105.0682311856 2011 39355.4516513287 2012 38817.645352079 2013 38765.502608767 2014 38634.7928884349 2015 37348.4284459628 2016 36958.8718020483 2017 38556.0521025032 2018 39943.358727869