1973

7.1

2008

6.0

2002

6.4

1996

8.0

2006

7.4

2001

4.3

1980

6.7

1973

6.1

1972

3.2

1976

5.5

1997

3.5

2018

6.0

2012

5.9

1970

6.4

1938

0.0

2004

5.0

1971

5.1

1995

3.9

1970

5.5

1966

5.2