Year including construction (constant 2015 US$) 1991 15861.838391745201 1992 16898.652680691004 1993 17063.318596623478 1994 16971.60645733551 1995 19519.27221715551 1996 20096.74497910573 1997 21662.38280216276 1998 24362.576206317714 1999 25432.07278460175 2000 27122.947844107377 2001 31418.027261257215 2002 31406.930599335188 2003 31825.113179425407 2004 32560.47993903964 2005 32651.869534639303 2006 34597.105815869436 2007 33914.39484649658 2008 34237.36341137976 2009 32286.435473680172 2010 33460.024434803476 2011 35048.58914366709 2012 35622.19251037778 2013 34515.53822584129 2014 34763.712679003984 2015 35234.08406186553 2016 36251.75707729068 2017 36248.20654145908 2018 36465.06686131963 2019 36457.47163579764 2020 36281.68741538183 2021 38001.54493167891 2022 39767.091872941666