1981

6.5

2010

6.6

1999

7.2

1964

7.2

2001

6.6

2017

6.6

2017

8.0

2017

6.9

2012

6.3

2006

7.4

1980

5.5

1994

7.9

1990

6.1

1992

5.0

2014

8.0

1996

6.0

2015

6.6

1931

6.9

2014

6.4

1961

8.0