1975

6.7

1973

4.8

1975

6.8

1977

6.8

2008

5.7

1972

6.7

1976

6.2

2001

5.9

2003

5.7

1988

7.3

1989

5.8

1983

7.2

1973

5.6

1974

4.3

1979

6.3

1977

5.2

2008

4.8

1992

5.2

2009

6.1

1973

4.0