2004

5.6

1987

7.3

1999

6.8

2001

7.6

1998

6.6

2005

6.8

2006

7.1

1999

7.8

2003

7.2

2001

6.7

2006

6.3

2001

7.4

1991

5.9

1989

7.0

1995

6.5

2003

6.4

1990

6.7

1994

7.0

1981

5.0

1996

6.6