1972

8.7

1988

7.4

2019

8.1

1994

8.7

2002

7.7

1994

8.3

2013

8.0

1999

7.6

2015

7.0

2018

7.6

2006

7.8

2001

7.9

2001

8.5

2007

7.3

2018

7.3

2008

8.5

2017

7.8

1995

8.4

2000

7.1

2018

7.0