1959

6.1

1989

7.1

2017

6.6

2000

6.7

1989

6.3

1995

6.2

2013

6.5

1952

6.7

1967

6.1

2012

7.2

1975

6.4

1989

5.5

1991

6.2

1933

6.2

2003

6.6

1990

6.1

1994

6.2

2002

6.1

2007

5.5

1976

4.5