1993

8.0

2000

6.1

1998

7.0

2000

7.4

1989

5.8

2006

6.6

1987

7.5

1998

6.4

1999

7.9

2006

8.1

2011

0.0

2019

5.0

2019

5.2

1994

7.7

1988

6.7

1978

8.2

2012

5.0

2005

7.4

2019

0.0

2013

6.6