1927

8.1

2002

7.5

2000

8.2

1994

8.3

2003

7.8

1999

7.0

2005

7.8

1930

7.7

1987

7.3

2007

6.7

2005

4.7

1974

6.3

1992

6.9

1979

6.1

2017

7.0

2005

5.7

1997

5.9

1999

7.4

1989

6.8

1998

7.1