1994

3.6

1998

6.9

1979

2.0

2005

6.3

1989

7.1

2006

5.6

1991

6.5

1984

8.0

2005

6.8

2014

3.0

1985

6.2

2006

6.5

1997

7.0

1989

4.0

2005

6.2

2013

5.2

2007

5.3

1996

7.6

1999

4.3

2006

7.6