Woe is GDP

The metric Gross Domestic Product has been under fire lately, more so than usual.

I’m not enough of an expert to evaluate the technical aspects of the debate, but this commentary caught my eye:

The basic problem is that gross domestic product measures activity, not benefit. If you kept your checkbook the way G.D.P. measures the national accounts, you’d record all the money deposited into your account, make entries for every check you write, and then add all the numbers together. The resulting bottom line might tell you something useful about the total cash flow of your household, but it’s not going to tell you whether you’re better off this month than last or, indeed, whether you’re solvent or going broke.

Because we use such a flawed measure of economic well-being, it’s foolish to pursue policies whose primary purpose is to raise it. Doing so is an instance of the fallacy of misplaced concreteness — mistaking the map for the terrain, or treating an instrument reading as though it were the reality rather than a representation. When you’re feeling a little chilly in your living room, you don’t hold a match to a thermometer and then claim that the room has gotten warmer. But that’s what we do when we seek to improve economic well-being by prodding G.D.P....

Given the fundamental problems with G.D.P. as a leading economic indicator, and our habit of taking it as a measurement of economic welfare, we should drop it altogether. We could keep the actual number, but rename it to make clearer what it represents; let’s call it gross domestic transactions. Few people would mistake a measurement of gross transactions for a measurement of general welfare. And the renaming would create room for acceptance of a new measurement, one that more accurately signals changes in the level of economic well-being we enjoy.

[From Eric Zencey,  G.D.P. R.I.P., New York Times op-ed, 8/9/2009]

The author of the article does not propose a new measurement, although the latest commission on the subject proposes a path to creating supplementary metrics.