1977

7.7

2000

7.1

2004

8.0

2005

7.4

1961

7.7

1999

7.0

2007

5.4

1976

7.8

1979

7.3

1982

6.9

1985

7.1

1990

5.8

1952

5.6

2002

7.3

2002

6.3

2018

6.4

1992

3.3

1988

7.5

1988

6.6

2004

6.8