1970

6.0

1995

7.3

1998

0.0

2002

6.9

1950

6.8

1988

5.9

1977

7.4

1996

6.7

2001

6.8

2000

7.1

2007

6.9

1997

3.9

1976

4.3

2017

4.5

1985

7.2

2002

4.9

1991

6.0

1980

5.6

1933

0.0

1970

7.2