Year including construction (constant 2010 US$) 1991 3617.83868326724 1992 3438.45639454254 1993 3020.30476786542 1994 2670.95962414736 1995 2309.42248488411 1996 2078.75885574165 1997 1843.22767033371 1998 1596.21076056428 1999 1421.72889224272 2000 1470.05428885987 2001 1476.42552618905 2002 1470.9087626133 2003 1475.31790169292 2004 1450.26978797211 2005 1453.88003110374 2006 1477.93280870213 2007 1492.83249088723 2008 1445.89795111615 2009 1395.886489236 2010 1400.82267398555 2011 1426.35952239665 2012 1435.67744452178 2013 1440.79507141403 2014 1494.47851928518 2015 1481.38302330585 2016 1369.22012926317 2017 1447.57556163669 2018 1503.80981768547