1989

5.5

1996

6.5

1996

5.8

1988

6.1

2003

6.3

1994

6.2

1959

6.1

2002

7.5

1987

5.2

2003

6.8

1943

6.4

2010

7.0

2013

6.5

1992

6.3

1971

5.9

2016

6.7

2017

6.5

1990

6.1

2009

4.8

2019

6.5