| 年度 | 实际值 |
|---|---|
| 1995 | 29.6 |
| 1996 | 34.4 |
| 1997 | 39.59 |
| 1998 | 49.6 |
| 1999 | 51.2 |
| 2000 | 43.7 |
| 2001 | 41.76 |
| 2002 | 40.31 |
| 2003 | 39.94 |
| 2004 | 38.17 |
| 2005 | 29.71 |
| 2006 | 58.63 |
| 2007 | 58.19 |
| 2008 | 64.98 |
| 2009 | |
| 2010 | 62.01 |
| 2011 | 54.57 |
| 2012 | 56.12 |
| 2013 | 58.27 |
| 2014 | 62.78 |
| 2015 | 64.83 |
| 2016 | 67.31 |
| 2017 | 69.4 |
| 2018 | 68.3 |