Long-term statistical data was explored, acquired, processed, and analysed in order to assess the historical domestic production and international trade of a number of cobalt-containing commodities in the EU. Different data sources were examined for data, such as the British Geological Survey (BGS), the US Geological Survey (USGS), and the Eurostat and UN Comtrade (UNC) databases, considering all EU-member states before and after they joined the EU. For the international trade, hidden flows related to data gaps such as data reported in monetary value or recorded as “special category” were identified and included in the analysis. In addition, data from the Finnish customs database (ULJAS) was used to complement flows reported by Eurostat and UNC. From UNC, data was obtained considering the member states as reporters or as partners of the trade, due to internal differences of the database.

Based on the acquired data the domestic production and international trade of the commodities were reconstructed for the timeframes 1938–2018 and 1988–2018, respectively. Next to the analysis of the trend of the production and trade of the different commodities, the importance of including hidden flows was revealed, where hidden flows represented more than 50% of the flow of a year in some cases. In addition, it was identified that even from reliable data sources, strong differences (more than 100% in some cases) can be found in the reported data, which is crucial to consider when utilizing the data in research.

探索、获取、处理和分析长期统计数据，以评估欧盟许多含钴商品的历史国内生产和国际贸易。考虑到所有欧盟成员国加入欧盟之前和之后，对不同数据源的数据进行了检查，例如英国地质调查局 (BGS)、美国地质调查局 (USGS) 以及欧盟统计局和联合国商品贸易统计数据库 (UNC) 数据库. 对于国际贸易，识别出与数据差距相关的隐藏流量，例如以货币价值报告或记录为“特殊类别”的数据，并将其纳入分析。此外，芬兰海关数据库 (ULJAS) 的数据用于补充欧盟统计局和联合国统计局报告的流量。从 UNC 获得的数据是将成员国视为报告者或贸易伙伴，

根据获得的数据，分别重建了 1938-2018 年和 1988-2018 年的国内生产和国际贸易。在分析不同商品的生产和贸易趋势后，揭示了包含隐性流量的重要性，在某些情况下，隐性流量占一年流量的 50% 以上。此外，即使来自可靠的数据来源，报告的数据中也可以发现很大的差异（在某些情况下超过 100%），这对于在研究中使用数据时至关重要。