2018
4.54%
2017
3.99%
2016
3.92%
2015
3.83%
2014
4.17%
2013
3.98%
2012
3.66%
2011
4.45%
2010
4.69%
2009
5.04%
2008
6.03%
2007
6.34%
2006
6.41%
2005
5.84%
2004
5.87%
2003
5.83%
2002
6.54%
2001
6.97%
2000
8.05%
1999
7.44%
1998
6.94%
1997
7.6%
1996
7.81%
1995
7.93%