1989

6.9

2006

8.2

1994

7.8

1996

6.8

1999

8.2

1994

8.4

1990

5.1

2004

7.4

1997

4.4

1992

6.7

2007

6.7

1994

2.6

1995

6.5

1998

7.1

2002

7.3