1935

7.4

1991

8.3

2003

6.5

2003

7.7

2006

5.4

2001

6.1

1999

7.5

1996

6.4

1946

7.6

1968

7.2

2004

7.1

1984

7.1

1990

6.4

1998

5.6

1973

6.9

1941

7.7

1925

7.1

1971

7.1

1966

7.4

1999

7.0