Year including construction (constant 2010 US$) 2007 58598.9003395171 2008 53438.9225808696 2009 49272.7199512152 2010 45858.8653845342 2011 45868.1784241614 2012 44716.1874164399 2013 48405.0138917886 2014 50062.3219808935 2015 49662.2175968114 2016 48407.8805311418 2017 45840.6293034006 2018 43643.9134881285