1973

3.2

1986

5.6

1981

6.5

1985

5.0

1989

7.2

1980

1.0

2006

5.3

2011

5.0

1986

6.3

1992

7.4

2003

0.0

1997

5.7

1993

6.4

1979

3.5

2018

5.1

1976

5.8

2003

3.0

2003

0.0

1986

5.8

1978

5.9

1991

5.9

1988

6.9

2009

4.6

1991

5.7

1978

2.9