1994

6.6

1991

6.2

1996

5.8

2013

6.1

1997

7.6

2015

6.9

2008

6.3

2012

6.4

2003

6.3

2010

7.7

2012

7.2

1988

6.5

1985

5.3

2005

7.1

1966

6.4

2009

6.1

2019

5.4

1977

6.3

2003

5.7

2013

6.6