1947

6.7

1994

6.1

1976

7.8

2007

5.6

1982

7.1

1999

4.2

1997

7.1

1998

7.1

2000

6.8

1981

6.5

1983

7.1

1975

6.5

1985

6.5

1971

4.5

2005

6.7

2003

6.7

1992

7.1

2000

1.7

1988

4.5

1977

3.0