“…One of the main features of the WSS is the availability of matched employer-worker microdata, which is particularly useful for the study of wage determination (Abowd & Kramarz, 1999;Hamermesh, 2008). In this sense, the WSS provides comprehensive information on firms with ten or more workers (WSS 2006 also includes firms with fewer than ten workers), classified in one of the following productive sectors: industry, construction, trade, catering, transport and communications, financial intermediation, real estate and leasing, business services, and, with the exception of WSS 1995, education, health, and other social activities.…”