2015

8.5

2010

6.6

2011

7.1

2010

7.0

1989

7.8

1962

7.9

1987

6.2

1923

6.7

2007

7.6

2013

6.7

2014

7.7

6.3

1955

7.2

1995

6.1

2015

5.5

1928

7.9

7.8

1975

6.5

1947

7.0

2015

6.1