1960

8.4

1996

6.6

2002

7.1

2005

7.8

2005

6.3

2001

7.4

2013

5.4

1997

6.1

1973

5.4

1965

6.1

1968

5.4

1930

6.8

1964

5.7

1984

3.3

1990

5.7

0.0

2002

6.6

2002

6.3

1992

5.4

2006

6.8