2017

4.1

1997

5.9

2006

6.6

1987

6.9

2002

6.7

2005

6.7

2002

7.3

1929

6.5

1994

5.6

1967

7.1

1996

6.7

1992

6.9

1993

5.4

2003

6.4

2004

6.9

1970

6.1

2001

4.8

2012

7.0

1975

7.3

2001

6.9