To curb tax-motivated income shifting and limit tax competition, the G20/OECD Inclusive Framework on Base Erosion and Profit Shifting (BEPS) has pursued a global reform of the taxation of large multinational enterprises (MNEs), which 141 jurisdictions have endorsed. The agreement in principle includes a minimum tax of 15 percent for the largest MNEs (Pillar II).
Ongoing discussions generally focus on its implications for corporate income tax revenues. Less is known about the effect of a minimum tax on the overall tax rate paid by MNEs on foreign direct investment (FDI) income, which ultimately drives investment decisions. We contribute to filling this gap.
EXISTING METRICS OF CORPORATE INCOME TAX RATES
There are 2 broad classes of corporate income tax rates:
statutory tax rates (STRs), established by law,
effective tax rates (ETRs), indicating the tax rate at which profits are “actually” taxed.
ETRs are are best suited for studying the taxes paid on FDI for 2 related reasons. First, ETRs give a more accurate picture of corporate income taxation. Unlike STRs, they absorb credits, deductions, exemptions, and other tax breaks granted by governments to lighten corporate income taxation. Second, ETRs better reflect the tax aggressiveness of offshore financial centers (OFCs). The difference between STRs and ETRs is most pronounced in OFCs due to greater resort to fiscal incentives and preferential tax treatment (see figure 1).
ETRs can be either backward-looking or forward-looking. In our analysis, we use backward-looking ETRs (for reasons explained in the paper). We also disregard within-country variation in ETRs and focus on average ETRs.
Backward-looking (average) ETR in host country c is defined as: