1979

6.7

1992

7.0

1989

7.3

1964

7.4

2005

7.5

2009

6.6

1987

5.7

1932

5.5

1969

7.1

1952

7.0

1928

6.9

1990

6.4

1989

5.2

1986

5.8

2013

7.6

1985

6.1

1958

7.6

1992

7.7

2009

6.2

2007

5.1