1973

4.2

1947

6.0

1998

6.2

1927

7.3

2009

5.9

1994

5.3

1995

6.7

1942

6.6

1942

7.3

1984

6.3

1932

7.4

2001

5.4

1999

7.2

2006

6.1

1999

7.8

2004

7.8

1996

6.9

1992

6.6

1991

6.0

1998

6.5