The threat of short-term supply disruptions may matter for commodity prices, although their magnitude is hard to detect, for example due to anticipation, storage and to the relatively short duration of disruption events. This article explores global commodity returns for copper around labor strikes in Chile mines between 1910 and 2010. In the five days around strikes, copper display cumulative abnormal returns (CAR) close to 200 basis points (bps). Consistent with the threat of supply disruptions, the effect comes almost fully from strikes at larger mines (CAR≈ 500 bps). Moreover, the price-increasing effect of strikes is stronger when copper inventories are scarce, as measured by the interest-adjusted basis. Despite strikes being transitory events, we also find a mirroring appreciation of the USD/CLP commodity currency.

短期供应中断的威胁可能对大宗商品价格产生影响，尽管其严重程度很难察觉，例如由于预期、储存以及中断事件持续时间相对较短。本文探讨了 1910 年至 2010 年智利矿山工人罢工期间铜的全球商品回报。在罢工前后的五天内，铜的累计异常回报 (CAR) 接近 200 个基点 (bps)。与供应中断的威胁一致，这种影响几乎完全来自大型矿山的罢工（CAR≈500 bps）。此外，当铜库存稀缺（以利率调整基数衡量）时，罢工的价格上涨效应更强。尽管罢工是暂时性事件，但我们也发现美元/智利比索商品货币也出现了相应的升值。