1951

0.0

1968

6.9

1964

7.9

1972

5.1

1967

4.8

2003

5.9

1969

6.1

1965

7.5

1953

6.8

1963

5.8

1998

7.1

2001

7.5

2005

8.6

1977

7.0

1968

6.0