1990

6.6

1996

6.7

2004

7.2

1960

4.7

1972

7.4

2008

6.8

1992

6.6

1984

2.0

1993

6.9

1933

6.2

1967

6.8

1951

5.2

1975

10.0

1971

0.0

1929

6.6

1950

8.1

2002

7.1

1948

7.9

2016

6.2

1961

7.3