1979

4.8

1989

5.8

1983

7.2

2003

7.2

1978

4.3

2016

4.6

1998

6.4

1991

0.0

1999

4.3

2013

5.6

2000

6.4

1990

6.2

2004

5.2

1989

5.7

2005

5.0

2006

5.2

2006

4.4

1996

5.9

2009

2.2

2016

7.2