1990

3.5

2012

5.4

1994

5.1

2014

8.4

1987

5.7

1988

4.6

1998

5.2

2016

10.0

1992

4.8

1991

6.0

1991

6.6

1988

5.3

2012

7.2

1985

7.6

1987

5.9

2008

4.5