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Notes to Consolidated Financial Statements 2. Summary of significant accounting policies: Inventories. Inventories are valued at cost, not in excess of market. Cost is determined on the "average-cost basis, except for the cost of finished products carried by certain subsidiary companies which is determined "last-in, first-out" ("LIFO") basis. Inventories valued on the LIFO basis totaled 94,578 million and 50,037 million at December 31, 2017 and 2018, respectively. Had the "first-in, first-out" basis been used for those companies using the LIFO basis, inventories would have been 10,120 million and 19,660 million higher than reported at December 31, 2017 and 2018, respectively. 2017 2018 9. Inventories: Inventories consist of the following: 31 December ( Millions) Finished goods Raw materials Work in process Supplies and other 403,856 99,869 79,979 24,868 608,572 291,977 85,966 83,890 24,632 486,465 49 The MD&A indicated that the prices of raw material, other production materi- als, and parts increased. Based on the inventory valuation methods described in Note 2, which inventory classification would least accurately reflect current prices? A Raw materials. B Finished goods. ( Work in process. 49 B is correct. Finished goods least accurately reflect current prices because some of the finished goods are valued under the last-in, first-out (LIFO") basis. The costs of the newest units available for sale are allocated to cost of goods sold, leaving the oldest units (at lower costs) in inventory. ZP values raw materials and work in process using the weighted average cost method. While not fully reflecting current prices, some inflationary effect will be included in the inven- tory values