The Revenue Consequences of Using Formula Apportionment to Calculate U.S. and Foreign-Source Income: A Firm-Level Analysis

This paper examines the 1989–1993 publicly available financial reports of 46 U.S.-based multinationals to estimate the revenue implications of implementing a U.S. federal formula apportionment system. Ignoring behavioral responses, we estimate shifting to an equal-weighted, three-factor formula would have increased their U.S. tax liabilities by 38 percent, with an 81 percent increase for oil and gas firms. We find the firms report a lower percentage of their worldwide profits as American profits than their American share of assets, sales, or payroll. The results may be attributed to more profitable foreign operations, tax-motivated income shifting, or measurement error.