1956

7.1

1994

4.8

1957

8.1

2015

6.7

1955

7.0

1986

7.3

2009

7.4

1988

5.5

1946

7.6

1943

7.5

1961

7.4

1964

7.2

1991

6.7

1989

6.7

1988

6.8

1992

6.7

1986

6.2

1989

5.7

1937

6.7

1995

6.5