1998

2.4

1975

2.7

1973

5.3

1970

5.5

2001

3.9

2002

3.3

1999

3.2

1989

4.2

1992

4.7

2000

5.4

1974

3.8

1971

6.0

1990

3.5

1996

4.6

1997

4.7

1999

5.2

2016

2.0

2002

6.8

1982

5.2

2008

5.1