INDUSTRIALPRODUCTION INDEX - Updating of the calculation basis

The monthly industrial production index is calculated using the chaining method introduced by the publication of the indices relating to the month of January 2022. From January 2025, the calculation base is set at the year 2024, while the reference base, in line with the other economic indicators, remains the year 2021.The methodological aspects and the main effects produced by the rebasing on the evolution of the indices are illustrated in this information note.

The innovations introduced, in continuity with the 2023 calculation base, concern the sources used, with an increase in the sectors for which the turnover volume indices are used, the updating of the sample of companies, the revision of the weighting system, the updating of the basket of goods.

The indices are calculated according to the Laspeyres formula using a weight structure updated annually. The indices, elaborated on the basis of calculation, are subsequently brought back to the reference base.

In the comparison between the weighting structures of the 2023 and 2024 calculation base, some variations in the weights for the different groupings emerge: a 0.4% drop in the incidence of both consumer goods and capital goods corresponds to an increase in that of intermediate goods (+0.6%) and, to a lesser extent, energy (+0.2%). As for the 2023 base, the sectors with greatest relevance for the industrial production index are the metallurgy and metal product manufacturing industry (16.4%) and the manufacturing of machinery and equipment not classified elsewhere (12.6%).

With the adoption of the 2024 calculation base, the product basket was also revised. Specifically, 83 products were eliminated, 65 of which were due to the integration of the survey data with those from the industrial turnover survey. At the same time, in order to increase coverage in the Ateco classes followed by the survey, 18 new products that had become significant over time were introduced. With the transition to the 2024 calculation base, therefore, the previous basket of 593 product macro-items was reduced to 584 items. With the exit from the basket of 38 macro-products, among the 29 that entered, 11 represent macro-product items that correspond to the indices of the economic activity groups detected by the turnover survey.

The industrial production indices starting from 1990 and up to the economic activity class level with a reference base of 2021=100 are published on the IstatData website at https://esploradati.istat.it. Calculation based data is available upon request.