1971

5.4

1965

6.6

1973

3.1

1981

3.3

1977

7.4

1966

4.3

1981

6.7

1990

6.4

2003

6.2

2005

5.8

1999

5.9

1998

5.4

1954

6.8

1999

6.0

1969

2.0

1997

6.1

2001

6.1

2014

3.4

1958

7.0

2004

5.2