1996

6.4

1993

7.7

2000

8.5

1995

7.6

2002

5.9

1999

6.5

1989

5.4

1988

6.6

1997

7.1

1984

7.2

1997

7.6

2007

6.3

1995

8.2

1990

5.5

2001

7.4