Year	current US$
2000	10.0156713
2001	10.20231941
2002	9.90042208
2003	11.57319978
2004	12.26800354
2005	13.99949895
2006	15.78693482
2007	18.022936
2008	18.54344167
2009	17.41850461
2010	17.78446046
2011	17.70885261
2012	20.45495444
2013	21.81492053
2014	21.38886656
2015	19.18003335
2016	18.56621592
2017	15.55248422
2018	17.67783464
2019	20.91427993
2020	20.08093131
2021	21.55509444