Seasonal Adjustment of Bank Deposits and Loans

Abstract:     
This paper illustrates the seasonal adjustment procedure for bank deposits and loans, focusing on the policy for the revision of seasonally adjusted data. Seasonal adjustment is semi-automatic when the commonly used software package, TRAMO-SEATS, is used to produce seasonally adjusted series. With reference to the frequency of seasonally adjusted data revisions, three alternative methods (current adjustment, concurrent adjustment, partial concurrent adjustment) are tested according to a quantitative criterion. A simulation study measures the speed of convergence of the estimates, obtained with these three updating methods, to reach a “final" estimate to be used as a benchmark. The results favour the use of the partial concurrent adjustment method, that suggests identifying the ARIMA model and the effects of the deterministic components once a year, and updating the corresponding coefficients once a month.

Number of Pages in PDF File: 39

Keywords: seasonally adjustment, partial concurrent adjustment

JEL Classification: C22, C87

working papers series