A well-designed chart is a powerful tool, able to transform intimidating numbers into an intuitive, instantly comprehensible, even beautiful visual form.
When things go awry, however, charts can be terribly misleading — even downright manipulative.
Here’s my pick for the most misleading chart of 2015. It was put together by an antiabortion organization called Americans United for Life, but it gained fame during a September congressional hearing, when Congressman Jason Chaffetz showed the chart to Planned Parenthood’s president, Cecile Richards.
At first blush, the chart seems to show a dramatic increase in the number of abortions performed by Planned Parenthood since 2006, alongside a steep decline in cancer screenings. Put together, the result looks like a reversal of priorities, with abortions having become the more common procedure.
But look closer at the numbers on the chart, and you’ll see that something is off. Even though the “abortions” line has crossed above the “cancer screenings line,” the numbers don’t match. According to the chart — and Planned Parenthood’s own records — Planned Parenthood performed 327,000 abortions in 2013 and nearly three times as many cancer screenings.
Clearly, something has gone terribly wrong with the y-axis, to let the purple line slip below the red one.
Here’s what the chart should look like.
Now that mathematical order has been restored — so that higher numbers appear further up the chart — the picture is quite different. It’s hard even to spot the increase in abortions, and while cancer screenings still seem to be on the decline, they clearly account for a larger part of what Planned Parenthood does.
As to why cancer screenings have been declining, there’s a very good reason: They don’t work — not as well as people thought back in 2006. Annual pap smears used to be considered best practice, but more recent guidelines suggest a longer waiting period between tests.
Even now, with the axis straightened out, there’s still a problem with this chart. After all, abortions and cancer screenings are hardly the only things Planned Parenthood does. It also provides contraception, STD testing, and prenatal services, just to name a few.
If the goal is really to figure out whether Planned Parenthood is devoting more of its resources to abortions, it makes better sense to compare the abortion numbers against the full basket of vital and largely uncontroversial medical services that Planned Parenthood provides. Like this.
Admittedly, this is not a captivating chart, particularly when compared to the eye-raising one that Chaffetz borrowed from Americans United for Life. But the reason it’s dull is because there isn’t much of a story. There haven’t been any dramatic ups and down, or big reversals, in the priorities or practices at Planned Parenthood.
That’s not meant to be definitive. If you are antiabortion, that Planned Parenthood continues to provide abortions at all is a horrific, ongoing tragedy.
But Chaffetz wasn’t making that point. He was trying to expose a surge in abortion activity — a surge that existed only within his chart. And that’s what makes it the most misleading chart of the year.
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Evan Horowitz digs through data to find information that illuminates the policy issues facing Massachusetts and the United States. He can be reached at email@example.com. Follow him on Twitter @GlobeHorowitz.