1927

8.1

1995

7.6

1985

7.7

2005

6.5

1982

6.7

1997

7.1

1999

8.2

2003

7.1

2003

6.7

1971

6.4

1984

7.7

2008

8.1

2016

5.7

2008

6.5

1976

6.6

1992

7.4

1994

6.3

2008

6.3

2006

5.8

2004

6.2