The industrial production index (IPI) is a statistical instrument used to monitor the monthly trends in France's industrial activity. If we refer to the traditional classification of economic activities in three sectors, the IPI concerns the so-called secondary sector: factories, construction sites, mines and quarries. The products monitored represent as well as possible the activity of the whole industry and are selected from all levels of the production process. These are Laspeyres indices (constant weighting) calculated by INSEE based on the data collected in the branch surveys by INSEE, the statistical data and studies service of the Ministry of Ecological and Solidary Transition, the SSP (Service for Statistics and Forecasts) of the Ministry for Agriculture and professional bodies. These indices are monthly and are corrected for seasonal variations and for working days.
The use is to speak of the index (singular) of industrial production when we are only interested in the macroeconomic indicator relating to the whole of industry or to manufacturing industry, and indices (plural) of industrial production when looking at the complete instrument describing both the evolution of the outputs of the industry as a whole, of sub-branches and of fine families industrial products.