2006

6.4

1999

5.9

2011

7.1

1992

6.3

1922

7.2

1996

6.0

1992

5.7

1988

5.2

1928

6.0

2000

7.5

1975

6.7

1974

6.0

1992

6.7

2010

7.3

2008

5.8

1989

5.3

1946

5.9

1982

6.7

2015

4.6

1990

6.3