Thomson Reuters GFMS recently updated the Q1 2015 copper cost curve data for its Copper Mine Economics report, and the Investing News Network was able to chat with Bruce Alway, base metals mining manager at the firm, to discuss the results. Based on its look at roughly two-thirds of global copper production, Thomson Reuters found that in Q1, net cash costs for copper were down 5 percent year-over-year, at $3,661 per tonne, while total unit costs, including depreciation, came in at $4,665, well below the current LME copper price. Costs were flat compared to Q4 2014. "It sounds quite low, but really you've got to be cautious in that number," said Alway. "That's a weighted average, so you've got some very low operations and some very high cost." Certainly, Thomson Reuters notes that the copper price has fallen faster than costs, meaning that margins have fallen 17 percent and higher-cost producers have been pushed into the red in terms of cash costs. Alway noted that net cash costs for the 90th percentile in Q1 came in at $5,051. That number increases to $6,126 with depreciation factored in, higher than Monday's LME copper price of US$5,948 per tonne. "It's the first time in a long time that you're actually losing money in the 90th percentile," Alway said. "It is an issue. It's getting tighter for the industry." Alway also spoke about some of the trends driving lower cash costs for producers. Here's a look at what he had to say. Low oil price Of course, as with many other commodities, a lower oil price has helped copper producers. Alway noted that copper costs make up between 5 and 20 percent of on-site production costs, but that the impact of cheap oil has been softer than one might expect — a cheaper price may take longer to have an effect due to existing contracts and on-site inventories, not to mention the fact that prices paid by miners are often higher than the contract prices quoted in the papers. "The fact that we saw cash costs down 3 percent despite a 41-percent drop in oil is not that surprising because there's not an immediate reaction," Alway stated. "But I do think that will be a positive in the next quarter and probably the quarter after that, oil price depending."