Year including construction (constant 2010 US$) 1991 28020.3888366032 1992 31593.2626090672 1993 26653.3038637399 1994 28393.3243086476 1995 29621.8036937944 1996 28775.7182265737 1997 30963.9700697368 1998 32009.8902083748 1999 33004.6081337918 2000 33421.7924226684 2001 31292.1459797027 2002 32481.420450242 2003 31636.0039759313 2004 34852.1367780981 2005 34816.8726733022 2006 39372.4587795155 2007 41102.9649795426 2008 42630.6066620209 2009 36802.5633550314 2010 41750.9977675492 2011 38566.5572718612 2012 37358.9756481226 2013 36508.0391767623 2014 36264.3022498804 2015 33013.8300726292 2016 28096.6363116579 2017 27309.7590410569 2018 24989.4394036257