1993

6.2

1988

5.4

1972

1.0

1980

2.0

1998

8.0

2000

5.7

1983

6.6

1970

4.1

1971

4.7

1968

4.5

1976

3.0

1989

4.5

1985

3.8

2012

2.3

2009

6.6

1995

3.8

1987

4.3

1977

5.6

1976

5.0

1970

5.7