Year including construction (constant 2015 US$) 1991 53601.240918564916 1992 55156.22742132431 1993 54141.93405261805 1994 56493.91516994098 1995 57173.67043494923 1996 57574.425090120785 1997 58158.62814236121 1998 60322.22062136369 1999 61922.503737376 2000 63539.928342293395 2001 64239.11503253884 2002 65424.299060941084 2003 67926.79028448417 2004 69276.65564754672 2005 71693.52538630787 2006 72402.67654589441 2007 74644.40263282742 2008 71229.09786961474 2009 69365.76889536533 2010 70854.54275693504 2011 72033.08666654926 2012 72510.02105362611 2013 74052.02281280991 2014 76865.99667470624 2015 77345.60841059267 2016 77233.87315151552 2017 77349.80014356459 2018 78760.43291534741 2019 79225.31365471007 2020 73561.76579539686 2021 76882.53902614574 2022 75246.34703489249