The survey was carried out in two waves focusing on the years 2005 (21 business sectors concerned - excluding clothing and footwear) and 2006 (16 remaining business sectors).

The collection method differed according to whether the enterprise surveyed was the head of a single network or several networks: paper questionnaire sent by post to the enterprises identified as being the heads of networks of a single listed network, and customised monitoring of enterprises at the head of several listed networks.

All of the listed network heads were surveyed, but only in the framework of their retail trade networks.

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The survey plan does not include a sampling plan: it exhaustively covers the field of networks of more than seven shops.

A database listing the networks (and network heads) was thus created on the basis of varied sources, both internal to INSEE (Annual Business Survey of enterprises in the trade sector, supplemented by the 2000 survey of chain store networks), and external networks (professional press and company websites).

This database was created with the cooperation of professional bodies.