Year including construction (constant 2015 US$) 1991 8160.104990779889 1992 8226.096242253934 1993 8011.051621018149 1994 7932.0183437433725 1995 8340.46592066696 1996 8337.814604294103 1997 8963.736447859486 1998 9154.684358186107 1999 9432.965731811202 2000 9807.815678894343 2001 9997.288538107472 2002 10286.10487406526 2003 10468.179459670007 2004 10875.86811257068 2005 11158.759022177914 2006 10797.459459752692 2007 10531.149118346126 2008 10607.638201956237 2009 9808.077154250594 2010 10808.551372355014 2011 11547.359994941653 2012 11886.36615433556 2013 11522.385406870755 2014 11801.97173290206 2015 11768.838105575049 2016 11998.624077533981 2017 12333.083375040469 2018 12334.117929103011 2019 12442.946269975746 2020 12235.969552605795 2021 12409.16545255009 2022 12146.902251972673