1987

7.3

2000

6.7

2017

6.2

1971

7.2

1991

4.9

2017

6.0

1983

4.5

1986

5.4

1983

5.1

1977

5.0

1983

7.6

2004

6.3

1989

6.1

1963

7.0

1992

6.3

1979

5.8

2016

6.9

2007

8.0

2011

6.5

2006

7.8