1988

6.2

2005

6.1

2004

6.9

2003

7.0

2017

6.2

1990

6.7

1998

6.6

1990

6.5

1999

5.3

2000

6.4

1960

6.1

1974

2.7

2005

0.0

1949

0.0

1990

7.5

2001

5.4

1950

7.3

1969

7.7

2021

6.6

2015

7.8