Year including construction (constant 2015 US$) 1991 294117.44287684065 1992 301637.4256610018 1993 296202.1413705317 1994 303703.14204290236 1995 306646.4864305035 1996 316554.3681883319 1997 293861.42721676326 1998 288246.5313668858 1999 298760.47610071104 2000 298446.49054239003 2001 290890.46657336026 2002 300105.2368396816 2003 307414.2010040393 2004 304584.14749896043 2005 298483.24195935886 2006 304015.47246014164 2007 286691.948183297 2008 270540.7828207637 2009 257571.8730022612 2010 261661.35094463167 2011 267663.7681037055 2012 265392.4803407911 2013 253782.58547753992 2014 247445.31959483583 2015 252076.941407028 2016 250828.72262001844 2017 259035.98002937666 2018 201673.88222752642 2019 193145.5898599701 2020 174940.192287609 2021 161985.15550629955 2022 146241.1047825021