1999

6.8

1998

6.6

1993

5.5

1996

6.6

2002

7.0

2001

6.7

1995

6.6

2002

7.2

1994

7.0

2005

6.7

2006

7.1

1999

7.7

2001

6.7

2006

6.2

2001

7.4

1991

5.7

1989

6.9

1995

6.4

2003

6.5

1990

6.5