1949

7.7

1989

5.1

1994

4.5

2006

7.0

1952

6.7

1968

6.4

1972

7.1

1965

7.6

1939

7.5

2002

7.4

2002

7.6

2015

6.3

2009

7.0

1962

7.7

1966

7.2

1990

7.5

1985

6.2

1953

7.4

2009

7.3

1977

6.7