Hi, the supplier performance database has become a necessity nowadays. Some do it systematically while others do it informally. But still, it is being done. What I can suggest is:

1) First, classify your suppliers according to a certain standard classification that is industry-specific rather than product-specific. One way is to classify them according to NAICS. Try to google myprocurementforum. It has a supplier database that is classified according to NAICS. It helps you identify where the supplier is positioned along the supply chain.

2) After that, you can now formulate your performance evaluation system. It can be done in three stages:
a) During the accreditation, when the supplier is evaluated based on what he can potentially do and what he has done with his other clients.
b) During the contract execution, when the supplier is evaluated by the contract implementors on the progress of the work.
c) When the contract ends. This becomes the summary of the evaluation for the supplier. It should include the recommendation on how to deal with the supplier in the next contract. Examples of recommendation:
- Maximum contracting capacity.
- Scope limitations.
- Change in payment or progress billing scheme.
- etc.

Usually, the rating starts with a PASSING (80%) by default. Then, a series of questions will add or subtract points from the PASSING rate, depending on the answers to the questions and how the answers affected the performance of the supplier.

There are some experts in the myprocurementforum. If you want, you can throw in your question.