1969

7.5

1998

6.6

2013

5.5

2018

5.1

1975

8.0

1993

6.6

1993

7.9

1980

7.1

2007

6.7

1995

7.0

1989

7.0

2014

6.0

1999

7.6

2007

7.6

1990

6.7

1966

6.5

2007

7.1

2016

6.6

1969

6.0

2018

1.0