1915

4.5

1970

5.5

1997

5.7

2001

6.9

1997

6.6

2001

6.4

1970

4.5

2007

5.3

1985

7.8

2005

6.2

1982

6.1

1995

6.3

1999

5.3

2014

5.4

1982

6.2

2001

7.5

2006

5.2

2003

6.2

1980

4.8

2007

6.9