2006

4.3

1999

4.9

1988

2.9

1993

7.1

2004

5.1

1992

5.8

1996

6.2

1995

7.3

1997

3.5

1987

4.5

1987

7.7

2002

7.9

1990

6.4

1988

3.9

1998

2.5