1983

6.7

1991

6.4

2008

7.2

1998

8.3

1999

7.4

1992

6.6

1980

0.0

2010

0.0

2014

6.4

2014

6.9

1982

5.8

1984

1.0

1994

6.8

2009

6.7

1975

6.5

1997

6.6

2006

5.5

1932

7.0

2014

7.8

1976

0.0