Abstract Calculating the cost-per-use of serials is a common practice in academic libraries, but the accuracy of these calculations requires accurate, comparable usage counts, and shortcomings of previous standards have made obtaining such counts difficult. Librarians may also want to exclude some uses, for example of open access articles, from their cost-per-use calculations, but these uses have often been difficult to identify. This column discusses two recent developments, the adoption of COUNTER Release 5 and the release of an online tool called Unsub, that will lead to improvements in usage counting and a significant readjustment of cost-per-use calculations for many libraries.

中文翻译：

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重新校准每次使用成本：COUNTER 第 5 版和取消订阅的影响

摘要 计算连续出版物的使用成本是学术图书馆的常见做法，但这些计算的准确性需要准确的、可比较的使用计数，而先前标准的缺点使得获得此类计数变得困难。图书馆员可能还想从每次使用成本的计算中排除某些用途，例如开放获取文章的用途，但这些用途通常难以确定。本专栏讨论了两项最新进展，即采用 COUNTER 第 5 版和发布名为 Unsub 的在线工具，这将改进使用计数，并对许多图书馆的每次使用成本计算进行重大调整。