1999

7.4

2004

8.2

2014

5.8

2006

8.2

1997

8.3

2002

8.6

2000

8.0

2010

8.1

1988

8.3

2019

7.1

1986

7.7

2007

7.5

1984

6.9

1994

8.4

2015

8.7

1987

7.5

1984

7.4

1991

7.4

2005

7.0

2005

7.8