1979

4.8

2013

7.5

1977

7.2

2007

6.4

1982

4.6

1998

7.2

2001

6.1

2001

7.3

2005

6.8

2006

6.1

2006

7.1

1971

0.0

1963

7.6

2005

5.3

1952

8.3

2016

7.0

2007

0.0

2007

6.3

2002

7.8

2007

5.5