1997

6.5

1994

3.2

2003

6.1

1990

6.8

1978

4.0

1979

5.0

1996

2.4

1989

4.5

1990

3.4

2003

8.0

1973

3.6

2005

5.6

2001

6.2

1995

6.4

1984

1.5

1980

6.4

1961

4.8

1972

6.3

1971

0.0

1982

1.7