1997

7.1

1999

8.2

2003

7.1

2003

6.7

1971

6.4

1970

6.1

1971

6.4

1972

6.2

1973

5.7

2002

6.6

2004

6.4

2005

6.7

2002

6.6

1994

6.3

2008

6.3

1996

4.1

1992

6.1

1973

6.9

1997

7.6

1972

6.4