| 1990 | 1991 | 1992 | 1993 | 1994 | 1995 | 1996 | 1997 | 1998 | 1999 | 2000 | 2001 | 2002 | 2003 | 2004 | 2005 | 2006 | 2007 | 2008 | 2009 | 2010 | 2011 | 2012 | 2013 | 2014 | 2015 | 2016 | 2017 | 2018 | 2019 | 2020 |
| 7,665.28 | 7,829.11 | 8,152.68 | 8,353.99 | 8,396.40 | 8,899.32 | 9,433.75 | 9,560.05 | 10,125.89 | 9,802.47 | 10,194.35 | 10,092.03 | 11,137.05 | 11,556.47 | 11,922.42 | 12,559.07 | 14,763.96 | 14,457.16 | 14,280.52 | 15,930.86 | 15,545.66 | 16,842.98 | 17,205.19 | 17,898.43 | 19,028.25 | 20,151.01 | 23,569.93 | 18,880.31 | 25,590.49 | 26,861.32 | 26,929.92 |