1999

6.8

2003

8.2

2001

5.9

1991

7.1

1994

7.4

2003

7.2

1990

6.5

2010

1.0

2001

7.5

1979

6.0

2004

4.6

2008

5.2

1982

6.1

1969

4.8

1995

6.1

1968

5.4

2007

7.2

2020

5.1

2005

5.0

2010

3.9