Year including construction (constant 2015 US$) 1991 3030.0649866401486 1992 3031.6065523150896 1993 3092.1035598492285 1994 3266.6156663170736 1995 3470.443120784176 1996 3507.9672634984345 1997 3504.3636637783557 1998 3470.696217246833 1999 3469.439016348346 2000 3525.0116854821595 2001 3495.2480405193414 2002 3645.1211801691406 2003 3740.2487615364166 2004 3935.236010702548 2005 4160.566289714523 2006 4462.543400456403 2007 4526.839131515171 2008 4468.802400517268 2009 4553.965441557899 2010 4593.670021547416 2011 4486.19453687785 2012 4378.300234738499 2013 4457.08417599918 2014 4670.083631667785 2015 5022.492990707867 2016 5295.3352370977045 2017 5517.550283834298 2018 5722.725095539769 2019 5546.295605541088 2020 5965.678480915574 2021 6210.6879976247255 2022 5642.268205862243