(in millions of euros)
December 31, 2017
December 31, 2016
Projects under construction, unsold
The inventories of maintenance materials consist of raw materials and other materials for the production and maintenance of semi-finished and finished products for the maintenance centres. In 2017, the write-down of inventories to the net realisable value, which was recognised as an expense, amounted to €10 million (€11 million in 2016). The cumulative impairment, after withdrawals, came to €97 million at the end of 2017 (€94 million at year-end 2016).
Inventories are stated at the lesser of cost and the net realisable value. The net realisable value is the estimated sales price in the normal conduct of business, less the estimated cost of completion and the cost of sales.
The cost of the inventories is based on the purchase prices or costs and includes expenses incurred in acquiring the inventories and the associated costs of purchase. The cost of inventories of finished products and work in progress includes a reasonable portion of the indirect costs based on normal production capacity.