1963

6.9

1973

7.4

1993

6.5

1967

6.7

1980

7.3

2015

6.1

1994

6.5

1966

6.1

1998

7.1

1995

4.6

2011

6.3

2003

7.3

1954

6.7

1993

6.6

1993

6.2

1999

6.2

1988

6.2

1988

6.5

1980

5.7

1987

8.1