1949

6.6

1939

6.3

1982

7.6

1999

7.4

1993

6.4

1989

6.8

2004

7.9

1970

7.5

2008

6.8

1974

6.9

2007

6.4

1982

6.4

1983

5.6

2008

5.1

1989

6.4

1988

5.0

2003

7.5

1984

5.6

2006

6.4

1980

5.3