2000

5.0

2011

6.2

1982

5.8

2002

5.7

1979

6.6

1975

7.3

1972

7.2

1993

6.8

1983

6.6

2007

6.7

1959

8.2

2015

8.1

2000

5.1

1999

5.1

1956

7.6

2009

6.7

1988

6.1

1999

6.7

1949

7.7

1967

6.9