1994

5.6

2004

5.9

1986

6.8

1966

7.7

1975

5.9

1980

5.9

1979

6.7

2003

6.5

1983

6.6

2006

3.8

1978

6.0

1985

5.9

2005

6.9

1992

6.5

2001

5.9

2003

5.7

1979

4.8

1968

6.5

1988

7.3

2019

6.4