Le système des comptes nationaux trimestriels

Un système de trimestrialisation des comptes nationaux annuels passés puis d'évaluation directe, pour les trimestres de l'année en cours, des principaux agrégats de ces comptes est mis en place à l'INSEE depuis trois ans. Il repose sur une comparaison systématique des évolutions des indicateurs conjoncturels et des comptes annuels au sein d'un modèle qui tente d'expliquer au moyen de la seule information conjoncturelle les niveaux retenus par les comptables nationaux au terme d'un dépouillement exhaustif de l'ensemble des séries d'informations économiques. Faisant appel aux techniques de la gestion intégrée de l'information le système a été entièrement informatisé et fonctionne de façon automatique. La publication régulière des premiers résultats de ces comptes a commencé en janvier 1973. /// For the past three years, INSEE has undertaken to implement a system of quarterly estimates of National Accounts main aggregates. Rather than operating quarterly simplified evaluations of the same kind as those carried out year by year, it was planned to compare systematically the evolutions of a great number of short-term indicators with those of the corresponding accounting aggregates, within a model in which annual accounts constitute the explained variable, and short-term information "the explanatory variable". Once this model has been estimated for a series of years, it is applied quarterly. It generates a series of quartely accounts which, summed up four by four, differ only from annual accounts by a deviation of zero expectation. Thus, for the current year, the computed quarters constitute an unbiased forecast of the year's future account. Likewise, quarters of past years differ from past annual accounts by an amount which represents the effect of the model's residual variable, that is to say of this fraction of annual accounts which cannot be explained by short-term information only. These deviations can, therefore, be distributed afterwards by a merely statistical procedure so that past quarterly accounts coincide exactly with past annual accounts. The interest of such a procedure consists in giving rise to systematic applications which can be computer-processed. For this purpose, a fully computerized system has been developed: it takes the input information from two data banks -- one of them contains all the annual accounts series, the other one, the whole set of short-term indicators -- and, after having processed these data, it generates a set of results f