Tax Effects on Productivity: An Economist's Personal Analysis

Harvard's Greg Mankiw turns his economist's microscope back on himself in the New York Times to uncover truths about productivity and taxation. To wit, if you tax something, you'll likely get less of it:

AN important issue dividing the political parties is whether to raise taxes on those earning more than $250,000 a year….

I have to acknowledge that the Democrats are right about one thing: I can afford to pay more in taxes. My income is not in the same league as superstar actors and hedge fund managers, but I have been very lucky nonetheless….

Nonetheless, as Republicans emphasize, taxes influence the decisions I make. I am regularly offered opportunities to earn extra money. It could be by talking to a business group, consulting on a legal case, giving a guest lecture, teaching summer school or writing an article. I turn down most but accept a few….

Suppose that some editor offered me $1,000 to write an article. If there were no taxes of any kind, this $1,000 of income would translate into $1,000 in extra saving. If I invested it in the stock of a company that earned, say, 8 percent a year on its capital, then 30 years from now, when I pass on, my children would inherit about $10,000. That is simply the miracle of compounding.

Now let's put taxes into the calculus. First, assuming that the Bush tax cuts expire, I would pay 39.6 percent in federal income taxes on that extra income. Beyond that, the phaseout of deductions adds 1.2 percentage points to my effective marginal tax rate. I also pay Medicare tax, which the recent health care bill is raising to 3.8 percent, starting in 2013. And in Massachusetts, I pay 5.3 percent in state income taxes, part of which I get back as a federal deduction. Putting all those taxes together, that $1,000 of pretax income becomes only $523 of saving.

And that saving no longer earns 8 percent. First, the corporation in which I have invested pays a 35 percent corporate tax on its earnings. So I get only 5.2 percent in dividends and capital gains. Then, on that income, I pay taxes at the federal and state level. As a result, I earn about 4 percent after taxes, and the $523 in saving grows to $1,700 after 30 years.

Then, when my children inherit the money, the estate tax will kick in. The marginal estate tax rate is scheduled to go as high as 55 percent next year, but Congress may reduce it a bit. Most likely, when that $1,700 enters my estate, my kids will get, at most, $1,000 of it.

HERE'S the bottom line: Without any taxes, accepting that editor's assignment would have yielded my children an extra $10,000. With taxes, it yields only $1,000. In effect, once the entire tax system is taken into account, my family's marginal tax rate is about 90 percent. Is it any wonder that I turn down most of the money-making opportunities I am offered?….

Now you might not care if I supply less of my services to the marketplace — although, because you are reading this article, you are one of my customers. But I bet there are some high-income taxpayers whose services you enjoy.

Maybe you are looking forward to a particular actor's next movie or a particular novelist's next book. Perhaps you wish that your favorite singer would have a concert near where you live. Or, someday, you may need treatment from a highly trained surgeon, or your child may need braces from the local orthodontist. Like me, these individuals respond to incentives. (Indeed, some studies report that high-income taxpayers are particularly responsive to taxes.) As they face higher tax rates, their services will be in shorter supply.

….don't let anyone fool you into thinking that when the government taxes the rich, only the rich bear the burden.

I have found that these sort of arguments have absolutely no impact on most people who want to soak the rich to help the state, but there it is, and it seems true.