Wednesday, October 9, 2013

Mulligan on Obamacare Marginal Tax Rates

Casey Mulligan wrote a nice Wall Street Journal Oped last week, summarizing his recent NBER Working Paper (also here on Casey's webpage) on marginal tax rates.

What do I mean, tax, you might ask. Obamacare is about giving people stuff, not taxing. Sadly, no. Obamacare gives subsidies that are dependent on income. As you earn more, you receive fewer subsidies for health care, reducing the incentive to earn more. Casey tots this sort of thing up, along with the actual taxes people will pay.

Economists use the word "tax" here and we know what we mean, but it would be better to call it "disincentives" so it's clearer what the problem is, and just how painful we make it for poor people in this country to rise out of that poverty.

As you can see, the average marginal "tax" rate went up 10 percentage points since 2007, and about 5 percentage points due to Obamacare alone.

Going back to the working paper, I think this is actually an understatement. (Probably the first time Casey or I have ever been accused of that!)

First, not even Casey can add everything up, and it all adds in one direction. State and local taxes, and vast number of state, county, city and other income or asset-based transfers all add. I haven't read all his papers or the whole book yet, but did Casey get them all? For example, I just got in the mail notice for a little program offered by the state of Illinois to lower your property taxes if you earn less than $100,000 per year. Nice, but one more little incentive not to earn more than $100,000 per year, and not in Casey's calculation.

In email correspondence, Casey pulled me back from these thoughts in a way that is revealing about the calculation. I wanted to add sales tax. After all, if you earn a dollar, but you have to pay 10% sales tax to do anything with it, that's another 10% distortion, no? Casey responds no, because he wants to measure the income-compensated distortion to labor, period. If you don't work, and somehow you also get income, you still have to pay the 10% sales tax. So the sales tax does not distort that pure work-no work decision. Casey's right, but I think this clearly illuminates the conservative nature of his calculation and what it means. There are a lot more margins, wedges, and distortions out there, and he's not trying to measure them all. He's also not trying to measure the wedges and disincentives for employers to hire people, towards non-market activities, and certainly not the effects of the regulatory tangle.

Another note of conservatisim: "The results account for the fact that many people will not participate in programs for which they are eligible." This is an important issue, that at least had not sunk in for me until reading a recent CBO report. People don't sign up for all the benefits to which they are eligible. If they did, marginal tax rates would be astronomical. It also sends a warning: Just how long will it be before people in an increasingly stagnant economy figure out all the programs they are eligible for?

Drawing a single line can also be unduly calming. You might say, "well 50% isn't so bad. Europeans still work, sort of, paying 50% marginal tax rates."  But as Casey reminds us, the spread in marginal tax rates across people is enormous. For example, the paper has a nice example (p. 13, table 2) of how a typical earner will come out ahead by choosing to work part time and receive subsidies, rather than work full time. This is a case of a 100% marginal tax rate.

It's likely that the effect of marginal taxes is nonlinear. Much of the labor decision comes in chunks: work or don't work; work part time or full time; apply for benefits or don't, with transactions costs and irreversibilities.  Suppose half the population feels a 100% marginal tax rate and half feels zero. Half the population works, half does not. That is likely a much larger effect than if the whole population felt a 50% marginal tax rate.

In sum, it's probably worse than even Casey's graph. But Casey is doing the right thing in putting up a carefully documented graph and paper rather than speculating. Speculation is for blogs, not papers and not for good opeds.

And Casey's big point remains the additional effect of Obamacare and other changes to Federal programs. Whatever you think the level is, it's now 10 percentage points more than what it used to be. On average.