Year including construction (constant 2015 US$) 1991 4390.13309523467 1992 4169.827310661415 1993 4031.0349761136263 1994 3970.987881175949 1995 4154.50036909888 1996 4558.944522086033 1997 4601.682922662926 1998 4405.004055037615 1999 4672.29357062593 2000 4325.605596266073 2001 4157.771634983445 2002 4791.797314701659 2003 4724.087859712871 2004 4980.403650853441 2005 5282.958145844504 2006 5527.903489348066 2007 5781.71370452531 2008 6129.99687613486 2009 6111.4043181447705 2010 6216.273473687875 2011 6104.308910729472 2012 5760.351859358274 2013 5751.962048911623 2014 5889.133246817439 2015 5877.733179910162 2016 6052.619857597646 2017 6203.2787160784865 2018 6329.061970957862 2019 6426.758469732668 2020 6217.206722422493 2021 6258.703467043268 2022 6393.92062356297