The incidence of income taxes on high earners in Canada

This article explores the “brain drain” explanation for the concentration of incomes in Canada during the past 30 years, namely, that high-skilled Canadians make use of high salaries on offer in the United States to extract higher salaries at home. If this is the case, then for a given level of US salaries, the threat to accept outside offers should be more credible when the Canadian dollar is depreciating against the US dollar, and weaker when the Canadian dollar is appreciating. The data are broadly consistent with this claim: income concentration worsened during the depreciations of the 1980s and 1990s, and eased when the Canadian dollar began to appreciate in value. The article develops a simple two-parameter model based on the propositions that high earners in Canada can use US salaries to bargain for higher salaries, and that Canadian high earners can shelter part of their income from personal income taxes. It also offers some preliminary evidence about the parameter values consistent with available data. The results suggest that higher top marginal personal income tax rates may potentially accentuate top-end after-tax income inequality. If high earners are able to use their bargaining power to extract pay increases to offset higher tax rates, then the burden of increased personal income taxes will be deflected elsewhere, and may even have the perverse effect of making the after-tax income distribution more unequal than it was before.