1996

6.9

1989

6.8

2000

8.0

2011

7.3

2000

7.9

2002

6.7

2005

8.2

2001

7.6

1994

3.5

1990

10.0

2003

7.2

2001

6.4

1984

5.8

1995

6.3

1998

6.8