用户反映 MC.9 的值与期望不符，经调试，发现居然采用了 S032 和 S031 两个表，也就是说数据源自 LIS：Logistics Information System。
The information systems used to plan, control, and monitor business events at different stages in the decision-making process.
The Logistics Information System is made up of the following information systems which all have a modular structure:
- Sales Information System
- Purchasing Information System
- Inventory Controlling
- Shop Floor Information System
- Plant Maintenance Information System
- Quality Management Information System
Tools are available in Customizing to allow a self-defined information system to be created and tailored to specific requirements.
简要来说，S032记录了库存物料的现值，S031记录了库存物料的发生合计数（根据日/周/月，因设置而异），据此倒推可得物料特定时间的库存状况。
LIS 聚集可能出现错误（我不知道原因），错误的修正也不简单。总而言之，用户这个问题，有待深入研究LIS后，同时他们能提供准确的参考数值后，放好解决。
SAP Note: 64636、512416、456106
MC.9 and MB5B both have the same Functionalities in terms of Stock Reports but main diff is MB5B will calculate stock based on the Tables ( MARD+MKPF+MSEG),but where as in MC.9 based on the Info Structures ( S031/32 etc ).
The logic is to retreive quantity from MSEG and count the stock programmatically.
Sometimes it can happen, if you activate negative stocks for the material and if you do goods issue postings before goods receipt posting.
Another reason is due to stock inconsistency in SAP info structures S031, S032 and S033.
Check the valuated stock in table MBEW for the particular matreial for which MC.9 shows -ive report.
you can use OLI2 transaction and program RMCBMMAT for repairing a single item.