1993

7.2

1994

7.5

2005

7.2

2002

6.1

2003

5.3

2018

6.9

2008

3.2

1982

7.3

1982

6.0

1963

4.0

1982

6.2

2006

7.6

2009

8.0

1991

2.0

1969

6.7

2009

5.0

1970

4.2

1985

6.1

1986

4.1

1997

7.3