1988

6.3

1990

6.1

2003

6.9

1993

2.7

2014

7.9

2005

7.0

1987

4.6

2012

6.4

2002

5.4

2007

6.4

2016

8.6

1993

7.5

1999

4.8

1997

6.2

2006

6.0