1996

5.8

1980

6.7

1997

6.1

2013

7.5

2013

7.9

1990

7.4

2012

6.2

1993

6.2

2008

6.5

2016

6.7

2015

6.6

1997

7.4

1995

5.6

1983

6.5

1993

5.8

2014

5.8

1976

8.1

2010

7.3

1994

8.5

1965

6.7