中文：

产成品库存指数是指企业成品库存与月平均销售收入的比率，它能够反映企业库存状况和资金占用情况。这个指数的计算方法是将企业月末库存成品余额除以月平均销售收入，再乘以100%。通过计算这个指数，可以判断企业的生产和销售是否协调，以及企业的库存管理水平和资金运用效率。

产成品库存指数过高，意味着企业生产出来的产品没有及时销售出去，导致库存积压，这会占用企业大量资金，增加企业的仓储和管理成本，甚至可能导致资金链断裂。而产成品库存指数过低，则表明企业生产与销售之间存在不协调，可能存在供应短缺或销售滞销等问题。

因此，企业需要合理控制产成品库存指数，以保持生产和销售的协调性，并提高企业的运营效率。一般来说，合理的产成品库存指数应该根据企业的实际情况进行评估和制定，同时需要加强库存管理和销售预测，提高生产和销售的协调效率，以实现产成品库存指数的优化控制。

英文：The finished product inventory index refers to the ratio of the enterprise's finished product inventory to the monthly average sales revenue, which can reflect the inventory status and capital occupancy of the enterprise. The calculation method of this index is to divide the enterprise's ending inventory of finished products by the monthly average sales revenue and then multiply it by 100%. By calculating this index, we can judge whether the production and sales of the enterprise are coordinated, as well as the level of inventory management and the efficiency of capital utilization.

If the finished product inventory index is too high, it means that the products produced by the enterprise have not been sold out in a timely manner, resulting in inventory backlog, which will occupy a lot of funds, increase warehousing and management costs, and may even lead to a breakdown of the capital chain. If the finished product inventory index is too low, it indicates that there is an imbalance between production and sales, which may lead to problems such as supply shortages or sales slumps.

Therefore, enterprises need to reasonably control the finished product inventory index to maintain the coordination between production and sales and improve operational efficiency. Generally speaking, a reasonable finished product inventory index should be assessed and set according to the actual situation of the enterprise. At the same time, enterprises need to strengthen inventory management and sales prediction, improve production and sales coordination efficiency, and achieve optimal control of the finished product inventory index.