| 年度 | 实际值 |
|---|---|
| 1992 | 38.37 |
| 1993 | 39.37 |
| 1994 | 39.53 |
| 1995 | 40.19 |
| 1996 | 40.9 |
| 1997 | 41.57 |
| 1998 | 47.65 |
| 1999 | 48.61 |
| 2000 | 50.7 |
| 2001 | 51.22 |
| 2002 | 51.55 |
| 2003 | 52.17 |
| 2004 | 52.21 |
| 2005 | 52.81 |
| 2006 | 52.58 |
| 2007 | 54.92 |
| 2008 | 55.73 |
| 2009 | |
| 2010 | 60.97 |
| 2011 | 62.7 |
| 2012 | 61.5 |
| 2013 | 62.6 |
| 2014 | 63.2 |
| 2015 | 63.97 |
| 2016 | 65 |
| 2017 | 65 |
| 2018 | 65 |