1998

7.1

2003

6.4

1995

6.5

1981

6.2

2006

5.3

2001

6.8

2000

7.1

1988

6.3

2006

5.4

2007

5.3

1998

7.0

1985

7.1

2018

6.5

1992

6.0

1993

6.7

2007

6.3

2004

6.3

1971

7.1

1965

7.2

2013

5.0