1999

6.1

2005

6.2

1980

8.2

2006

5.3

2003

7.2

1962

7.3

1998

6.6

1939

5.8

2004

6.0

2007

6.3

2003

5.8

1958

7.8

2000

6.3

1956

7.6

2005

7.3

2015

7.5

1953

6.9

1998

2.9

2007

6.7

2002

6.9