1999

6.8

2011

6.6

1993

6.5

2017

6.5

1993

6.5

2019

6.6

2012

6.4

2003

6.8

2009

7.2

1965

6.3

1993

6.6

2008

6.7

1982

6.7

1989

6.2

1985

6.1

2002

7.1

1988

5.2

1972

6.3

1967

6.1

1987

6.0