2003

8.2

1995

7.6

1989

8.3

1994

8.0

1999

8.2

1987

7.3

1993

7.0

2008

6.7

2017

6.5

2009

7.9

2002

7.5

2003

7.8

2010

8.1

2003

7.9

1993

7.7

2002

8.1

2001

8.0

2005

7.6

1960

7.4

2004

6.3