2006

6.7

1980

6.4

1994

8.5

2009

7.9

1965

8.0

2000

5.2

2004

7.9

2004

7.1

1981

6.6

2005

6.5

1999

5.9

1992

6.4

2004

7.0

1954

6.7

1993

6.2

2015

6.1

1974

6.5

2009

7.0

1990

7.5