1996

6.6

2002

7.1

2005

6.3

2001

6.7

1969

2.8

2002

4.8

1994

2.5

1995

6.7

2001

7.4

1991

5.9

1995

6.4

2003

6.5

1990

6.8

1994

7.0

2005

6.8

2006

7.1

1999

7.8

2003

7.2

2001

6.7

2006

6.3