1989

3.7

1982

6.0

1993

5.5

1973

6.4

2016

2.0

2002

6.8

1973

5.4

1994

4.5

2000

5.2

1992

4.7

1980

4.8

1974

3.8

1971

6.0

1993

6.3

1977

5.4

1996

4.6

1997

4.7

1999

5.3

2017

7.0

1975

5.8