Sales, other than sales of tangible personal property, are in this state if: 1. The income-producing activity is performed in this state; or 2. The income-producing activity is performed both in and outside this state and a greater proportion of the income-producing activity is performed in this state than in any other state, based on costs of performance.
Other sales
N.D.C.C. § 57-38.1-17 — under Uniform Division of Income Tax Act.
N.D.C.C. § 57-38.1-17