Data
1955 1960 1965 1970 1975 1980 1985 1990 1995
USA 27 28 30 33 39 43 49 53
Belgium 6.7 8.2 10.6 13.5 17 24 30 38
Japan 2.2 3.5 6.2 14 26 33 38 43
Hungary 1.8 2.3 2.8 3.6 4.6 5.2 6.6 8.6
S Korea 1.4 2.6 6 14 28