Data source(s) used: Istat economic sentiment indicator - IESI : Since June 2012, Istat disseminates the composite economic sentiment indicator of the whole Italian firms named IESI (Istat Economic Sentiment Indicator). Until April 2017, the indicator was calculated by aggregating of the balances of the variables included in the confidence climate indicator of industry (assessments on the order books, on the stocks of finished products and expectations on the production), of construction (assessments on current order books and expectations on firm's employment), of services (assessments and expectations on orders and expectations on the general economy), and of retail trade (assessments and expectations on business situation and assessments on stocks). Starting from the publication of May 2017, one of the series which makes up IESI was substituted. More specifically, with reference to the service sector, the balance series pertaining to the expectations on the general economy was replaced by the one concerning the assessments on the general business situation. That was done consistently with the new definition of the service climate confidence index. The calculation methodology of the indicator remains unvaried. The new series has been recalculated since March 2005.As for the calculation methodology, the 11 initial series are seasonally adjusted with the Tramo-Seats method and standardized. Their synthesis is obtained by a weighted average, using as weights the shares of the value added attributable to each sector. In order to get the weight to be assigned to each balance, the value-added of each sector is divided by the number of variables included in the computation of each confidence climate indicator. The weights used to synthesize the series refer to the year 2012 value added figures. The composite indicator obtained is converted into an index number based 2010=100.The previous series (2005=100) are weighted with value added figures referring to 2010. They was not calculated on the basis of the new definition of the service climate confidence index.