1985

7.2

2007

6.6

1989

6.6

1956

4.6

1979

6.0

2002

6.0

2007

8.1

2005

5.9

2007

7.1

1998

6.6

2006

5.8

2007

6.1

2009

7.1

1990

6.1

1983

6.3

1992

7.0

2003

6.9

2008

6.5

1940

4.3

2002

5.9