Methodology

Early Retail Sales Index

The ITV is elaborated using data on pedestrian traffic measured by URBIX in real time up to the 21st day of each month, in stores and/or common areas within some of the main shopping malls in the Greater Buenos Aires Area. Before the index is effectively calculated, URBIX checks the data for coherence and consistency. For confidentiality reasons, the name of the shopping malls where the data is gathered may not be disclosed.

In addition to the data on pedestrian traffic, the construction of the ITV also includes a binary variable to account for the seasonal variation in sales during the month of December, and a linear trend over time. The ITV is calculated based on its monthly percent changes, which are assumed to be proportional to the variation in pedestrian traffic and the other independent variables. The coefficients for these variables are calculated using the available historical data, through the estimation of a linear regression between the month-to-month variations of the independent variables, and contemporary, month-to-month variations of an appropriate measure of real consumption. Throughout the development of the ITV, the Shopping Center Sales at current prices published by INDEC, deflated by the Consumer Price Index reported by Congress (IPC-Congreso), has been used as a historical measure of real consumption. The ITV is then calculated based on its month-to-month percent changes, with an initial value of 100 in July 2012.