2000

6.2

2001

6.1

1969

6.8

1991

7.0

2003

5.7

2004

7.1

2007

9.8

1972

7.5

1998

6.4

2011

7.7

1993

5.5

1990

6.3

1980

6.7

1996

5.3

1969

6.4

2004

7.3

1997

5.4

1999

6.3

1986

6.8

2010

6.6