2000

7.1

2001

7.5

1987

7.6

1989

6.5

1996

5.9

1994

7.2

2000

7.1

2007

8.1

1973

6.2

2011

0.0

2001

7.4

1998

6.6

2008

8.5

1970

6.3

1990

6.1

0.0

1999

5.2

2005

4.8

1970

0.0

1999

6.5