1994

6.3

1997

6.2

1996

6.2

2006

6.2

1998

6.1

1988

6.3

1995

5.1

2018

6.6

1995

6.7

2001

7.4

1995

5.3

2007

6.1

2001

6.1

2002

6.2

2003

6.3

1995

7.0

2005

7.0

1991

6.3

1988

7.1

1989

6.8