1966

6.3

2006

6.1

1998

7.1

2004

5.7

1989

5.9

2013

3.0

2004

6.3

2006

6.0

1997

6.1

2003

6.1

2017

5.5

1913

5.3

2002

5.8

1968

6.5

1997

6.5

1980

6.4

1987

7.7

1941

7.2

1996

6.7

1989

5.3