1959

0.0

1975

5.5

2000

0.0

1964

7.4

1971

7.9

1988

5.8

1962

6.8

1974

5.8

1985

6.8

1975

7.4

1985

4.8

1972

7.5

1989

7.5

2003

9.1

1999

7.0

2005

7.3

2000

8.5

1983

7.6

1995

6.3

2004

8.4