Lousy labels
May 21, 2026 at 6:13 PM by Dr. Drang
In Paul Krugman’s post today, he includes two charts. One is fine, the other isn’t.
Here’s the first one:
Generally, I’m not a fan of putting stuff in the margins that could be within the body of the plot itself, but at least it’s clear which label goes with which data series. Too bad that’s not the case with Chart 2:
The two series end at almost the same spot, so putting the labels out in the margin means they can’t both be centered on their series. The little leader lines that run from the labels to the series match the colors of the series, but unfortunately, their colors are difficult to distinguish because
- The two colors are both shades of blue.
- The leader lines are thin, muting their colors.
- The leader lines are dashed, further muting their colors.
I’m not saying you can’t tell which is which, but when a chart is showing only two things you shouldn’t have to squint to tell the two apart. And it’s harder if you’re reading the article on a phone.
In the text just below Chart 2, Krugman says
The blue line labeled “Euro relative constant prices” supports the Draghi-Smith story of badly lagging European productivity, with Europe starting well above the US level but falling far behind. But the black line labeled “Europe relative current prices” shows Europe holding its own.
This is essentially alt text. It helps but would be better if there actually were a black line and not just a darker blue line.
Better still would be moving the labels so what they’re labeling is obvious. Something like this:
Yes, I should have pushed the upper label a little further to the left.
Charting software can’t judge the clarity of its output, but we can. A little touch-up in a graphics program can work wonders.