1989

5.4

2011

7.4

2006

6.6

1970

6.4

1978

6.9

2006

4.3

1985

5.8

2020

6.9

1959

7.1

1984

7.1

1996

5.3

2015

8.0

2012

6.5

1992

7.2

2009

5.3

1971

6.8

1966

6.1

2012

4.8

1993

6.5

1988

6.3