1985

7.8

2014

8.1

1981

6.5

1998

9.0

1986

8.4

1989

6.7

2004

8.3

2016

7.5

2015

7.3

1972

7.6

2016

7.7

1969

7.4

2009

7.6

2010

7.9

2013

8.1

1963

7.8

1994

7.2

2015

8.2

1973

7.6

1990

7.4