1962

6.9

2008

6.6

1979

5.6

1992

5.2

1984

7.2

1993

5.5

2018

7.9

2007

6.1

2007

6.2

2006

6.6

2005

7.1

1988

6.0

1925

6.7

1960

5.7

1992

5.2

1998

4.8

2001

6.0

1994

6.6

1956

6.6

2017

8.0