1995

5.9

2009

5.7

2004

7.1

2001

5.8

2009

5.8

2008

7.5

1937

7.2

1961

6.9

1988

5.7

2012

4.4

2008

5.3

1975

6.8

1989

5.5

1992

5.4

2003

7.3

1982

6.3

2009

4.4

1995

6.0

1951

7.5

1982

6.4