Year	% of lower secondary school age
1971	38.3949394226074
1972	30.5660305023193
1973	22.5116691589355
1974	23.8529796600342
1975	18.5858993530273
1976	18.3818607330322
1977	22.8817005157471
1978	22.9232692718506
1980	23.0337200164795
1981	18.3644599914551
1983	9.44643974304199