1990

6.2

1991

6.8

1939

6.9

1992

6.2

1982

6.7

2014

6.5

2006

4.7

1971

7.2

1944

8.1

1994

7.0

1993

6.3

1966

7.3

1983

5.9

1999

7.0

2003

7.1

2006

6.0

2006

7.2

2006

5.3

2008

6.6

2007

6.5