1993

5.5

1992

4.7

2000

5.2

1989

3.7

1973

5.4

1994

4.5

1974

3.8

1971

6.0

1990

3.5

1980

4.8

1975

5.8

1982

6.0

2002

6.8

2016

2.0

1973

6.4

2002

1.0

2017

7.0

2013

5.2

2005

3.6

1999

5.3