Thanks to reader Doug Magowan for bringing this to our attention.
In his New York Times blog “The Conscience of a Liberal“, the far-left economist Paul Krugman presented these graphs and this story (which I quote in full so that there is no ambiguity):
Special Bulletin: Fractions Have Denominators
I’ve been getting some mail over yesterday’s column, with angry correspondents posting charts like this, showing government spending as a percentage of GDP, to claim that government spending has too surged:
But if you look at the raw numbers on government spending, here’s what you see:
Feel the surge!
What’s going on? Yes, that’s right: it’s what happens when you divide by GDP in a time of terrible economic performance. Spending hasn’t surged; in fact, it grew more slowly in the two years after Lehman collapsed than in the two previous years, despite a sharp rise in spending on safety-net programs. Instead, GDP growth has plunged.
Notice anything funny about that second graph? Compare the vertical axis of it with that of the first graph. The first graph (spending as percentage of GDP) lets the data choose the range of the axis, from 30% to 37%. In the second graph, Krugman selects the axis range himself, from 0 to 6 trillion.
Here’s an estimate of that same second graph again, replotted letting the data chose the axis limits:
Feel the surge!
Why did Krugman—or whatever flunky he has plotting data for him—start at 0 trillion dollars for the second graph? Spending must, of course, start at zero dollars, but there is no good reason to do start the figure at that number except to hide a dramatic change in the data, and make it seem small or negligible.
Starting at 0 is a well known trick, and a good one. So wily it is that I don’t know why Krugman (or his flunky) didn’t try the same sleight of hand on the first graph, too. If he did, he could have got something like this:
Percentages start at 0, do they not? And they end at 100. Might as well set the limits of our graphs at these numbers, especially if we want to mask significant changes through time.
Sometimes it makes sense to start at percentage graph at 0, particularly when small percent changes translate into tiny actual-dollar shift. But here, a six-percentage point change is humongous because we’re talking trillions of dollars. Only a socialist would think this small change.
Of course, both of my recreations are estimates because I do not have the raw data to recreate them exactly. I do not capture the exponential percentage increase from 2009 to 2010, for example. But the actual-dollar spending graph is not too far off.
Krugman said, “Spending hasn’t surged; in fact, it grew more slowly in the two years after Lehman collapsed than in the two previous years…” He can make that statement only if tricked himself—or wants to tricks others. That is, either he’s lying to us, or is easily fooled by cheesy statistical tricks. There is no third explanation.
Note: at least one of the people commenting on Krugman’s blog noticed the shenanigans with the graphs, implying there is hope.