1949

6.2

2005

5.7

2006

6.7

1984

7.3

1965

7.6

2005

6.4

2005

6.8

2008

5.8

1989

7.8

1997

5.6

1969

5.1

2017

7.6

2003

6.6

2003

6.1

1951

7.7

1990

6.1

1972

6.2

1971

6.8

2002

6.0

1982

5.2