Keywords: Labour Cost; Administrative Data; Derived Variables.
Empirical analyses on the Italian labour market have largely benefited from the use of Social Security administrative longitudinal micro-data (INPS). However the individual's data, which are collected for administrative purposes, allow to know only a part of the information on workers, jobs or employing firms. Compulsory social security contributions and labour cost can be computed by INPS micro-data as shown by the ISTAT OROS survey on firm's contribution. This paper presents an experiment, currently limited to the period 1996- 2004, which aims at reconstructing information on social security contributions and labour cost in all its components using longitudinal micro-data from WHIP (Work Histories Italian Panel). Information on individuals and firms are integrated with the specific rules of contributions which apply to each sector of activity, firm size, geographical location and contract type. The results show that the obtained estimates are consistent with the official statistics.