2010

5.8

1969

6.6

2015

6.4

1998

5.4

2011

5.3

1987

6.5

2012

5.4

1979

6.2

1975

6.8

1971

6.4

1988

6.7

1973

6.5

1994

5.2

1996

5.4

1993

5.0

1989

6.9

1968

7.1

2007

7.2

2004

7.2

2013

6.1