Krugman Wonks Out: Why Doesn’t Cutting Taxes on the Wealthy Work?

So if tax cuts for the rich are like a wage hike, they could lead to less rather than more effort.

But wait: the top tax rate is a marginal rate, not an average rate. Individuals making, say, $600,000 a year pay 37 percent on the last dollar they earn, but most of their income is taxed at substantially lower rates — and those rates won’t be affected if President Biden succeeds in raising the top rate back to 39.6 percent. So you might think that raising or lowering the top rate is not, in fact, much like changing affluent Americans’ wages.

But here’s the thing: most of the earned income accruing to people in the top tax bracket is, in fact, taxed at the top rate. (Capital gains etc. are a different story.) Why? Because the distribution of income at the top is itself very unequal: there are huge disparities even within the economic elite. According to estimates by Thomas Piketty and Emmanuel Saez, almost half the income of the top 1 percent accrues to the top 0.1 percent, a category that begins at around three times as high a threshold.

Now, high incomes closely follow a Pareto distribution, indeed to an eerie extent. Here’s a plot of high incomes versus the percentage of taxpayers with incomes above that level, both expressed in natural logs:

Credit…Piketty and Saez

In such a distribution, the top .05 percent is to the top 0.5 percent what the top 0.1 percent is to the top 1 percent, so what is true of the distribution of income within the 1 percent is also true of the distribution within the roughly 0.5 percent of Americans subject to the top tax rate. This means that, as I said, most of the income accruing to that group is taxed at the top rate. And this in turn means that cutting that top rate is more like an across-the-board wage rise for the elite than you might think — and wage rises don’t tend to increase work effort.

Or to put it a bit differently, while tax cuts for the rich may offer an incentive to work harder, they’re also a big giveaway that encourages the elite to work less.

Of course, the fact that tax cuts at the top are a big giveaway is precisely the reason that belief in the immense economic importance of low taxes is such an unkillable zombie. As Upton Sinclair famously said, it’s difficult to get a man to understand something when his salary depends on his not understanding it.