(DSI) One line of source code (LOC) developed by a project.

DSI is the primary input to many tools for estimating software cost. The term "delivered" is generally meant to exclude non-delivered support software such as test drivers. However, if these are developed with the same care as delivered software, with their own reviews, test plans, documentation, etc., then they should be counted. The "source instructions" include all program instructions created by project personnel and processed into machine code by some combination of preprocessors, compilers, and assemblers. It excludes comments and unmodified utility software. It includes job control language, format statements, and data declarations.