1980

7.3

1999

6.3

2013

7.5

2006

7.0

1992

6.7

2007

6.4

2001

7.1

1993

6.2

2005

5.8

2000

6.4

2013

4.8

1988

5.9

2006

6.2

1987

7.3

1989

6.8

2002

6.4

1982

6.1

2019

7.5

2015

6.0

2000

6.6