Which SAP smart business KPIs are used to monitor contracts? Select the correct answer.

Contract leakage is a crucial KPI used to monitor contracts within SAP's smart business framework. This metric specifically focuses on the lost savings opportunities that arise when contracts are not adhered to as intended, resulting in higher than necessary spending outside of negotiated agreements. Monitoring contract leakage allows organizations to identify areas where compliance might be lacking and helps in enforcing the usage of negotiated contracts, ultimately driving better spending efficiency.

The other options, while relevant to various aspects of procurement and supplier management, do not directly assess contract performance in the way that contract leakage does. For instance, September spending pertains to a specific time frame and does not necessarily reflect the effectiveness of contract management. The annual vendor quality rating evaluates supplier performance rather than contractual adherence, and supplier negotiation scores may measure the effectiveness of negotiations but do not directly indicate whether contract terms are being followed.