2006

6.2

2008

5.4

1999

6.3

2007

6.2

2009

5.6

1983

5.5

1982

6.9

1989

6.5

1984

7.1

1960

7.5

1985

7.2

2001

6.2

1985

7.2

1990

6.0

1982

6.9

2007

7.2

2008

7.1

1980

6.6

2015

7.8

2008

5.6