The data come from the Institute's website Cattaneo.
1945 1.770.896 1946 2.068.272 1947 2.252.446
1948 2.115.232 1949 2.027.271 1950 2.112.593
1951 2.097.830 1952 2.093.540 1953 2.134.285
1954 2.145.317
1955 2.090.006 1956 2.035.353 1957 1.825.342
1958 1.818.606 1959 1.789.269 1960 1.792.974
1961 1.728.620 1962 1.630.550 1963 1.615.571
1964 1.641.214
1965 1.615.296 1966 1.575.935 1967 1.534.705
1968 1.502.862 1969 1.503.816 1970 1.507.047
1974 1.657.825 1975 1.730.453 1976 1.814.262
1977 1.814.154
1978 1.790.450 1979 1.761.297 1980 1.751.323
1981 1.714.052 1982 1.673.751 1983 1.635.264
1984 1.619.940 1985 1.595.281 1986 1.551.576
1987 1.508.140
1988 1.462.281 1989 1.421.230 1990 1.264.790
