This is not a question regarding the quality of the SLoC metric. I accept it as a limited, inaccurate, or even poor metric.
That said, I am looking for data that indicates what reasonable rates for software development given SLoC. Of particular interest are rates for different government agencies, but any insights will help.
Clarification
I have already developed a software application and it is ready to ship. The price was previously set by contract and is not in dispute. However, the accounting team is looking for a numeric reason to give their stamp of approval. These people do not account for skill or knowledge required, learning curve, generated code, efficiency or anything else. They have already been presented with valid metrics that show the "cost savings." We saved them 80%. But now we are required to justify the remaining 20%. They have been given other cost estimates, but that is not sufficient. So, I am trying to appease the bureaucracy with something to which it might relate.