Year	US Dollars
1997	510580411.89454
1998	529743042.51825
1999	548675289.73073
2000	598740718.97676
2001	658147170.3314
2002	695430552.05493
2003	713371108.55233
2004	782331935.13076
2005	810369295.32961
2006	837553464.30484
2007	917590753.19273
2008	941806843.47474
2009	918033522.68687
2010	957101573.7303
2011	1024939103.95493
2012	1037636885.98555
2013	1039059687.99497
2014	1074974833.18408
2015	1124104138.85301
2016	1215277418.89778
2017	1255570918.41239