1986

6.7

1968

4.2

1934

7.5

1967

6.7

2007

7.6

1965

6.3

2017

6.1

2007

2.0

1997

5.7

2006

6.5

2006

5.5

2003

5.9

1978

6.3

2003

5.0

1989

6.1

1989

6.1

1996

5.9

2003

6.8

2008

5.8

2008

6.7