1970

5.3

2011

7.4

2009

7.9

1946

7.8

1986

7.7

1968

6.9

2011

5.9

1987

7.0

1998

7.4

1985

6.4

2015

7.4

1987

7.2

1990

7.7

1969

7.7

1984

7.2

1966

7.5

1988

6.6

1969

7.3

1999

7.6

2004

5.7