| 年度 | 实际值 |
|---|---|
| 1992 | 38.2 |
| 1993 | |
| 1994 | |
| 1995 | 39.3 |
| 1996 | |
| 1997 | |
| 1998 | |
| 1999 | 40 |
| 2000 | 40.2997 |
| 2001 | 40.4187 |
| 2002 | 40.7836 |
| 2003 | 41.1644 |
| 2004 | 41.4795 |
| 2005 | 42.03 |
| 2006 | 42.01 |
| 2007 | 42.22 |
| 2008 | 42.268617084809 |
| 2009 | 44.3755 |
| 2010 | 45.0738 |
| 2011 | 45.5617 |
| 2012 | 45.834 |
| 2013 | 46.1027 |
| 2014 | 41.74 |
| 2015 | 41.8687305851503 |
| 2016 | 45 |
| 2017 | 45 |