1972

7.3

1999

6.3

1997

7.8

1984

6.1

2004

5.5

2006

5.0

1928

8.0

1974

6.4

1969

7.3

2009

7.5

1969

7.6

1987

4.7

1973

7.0

2008

6.6

1954

7.9

1987

5.5

1923

7.5

2004

6.8

2016

6.0

2016

6.3