1956

7.6

1991

6.4

1966

7.1

2002

5.4

1987

7.5

2001

7.3

1998

6.9

1997

6.8

1985

6.2

2005

6.7

2005

7.3

2000

5.3

2005

6.8

2000

7.2

2006

7.2

1999

6.6

2017

4.9

2002

6.7

2004

6.3

2005

6.9