Here at The Upshot, we love charts. And I have a chart to explain why.

But first, some background. In a study recently published in the journal “Public Understanding of Science,” two Cornell researchers, Brian Wansink and Aner Tal, ran a small online survey to assess whether alternative descriptions of the same information were more persuasive. Each respondent read the following description of a mythical drug trial:

“A large pharmaceutical company has recently developed a new drug to boost peoples’ immune function. It reports that trials it conducted demonstrated a drop of 40 percent (from 87 to 47 percent) in occurrence of the common cold. It intends to market the new drug as soon as next winter, following F.D.A. approval.”

When this was the only information given, 68 percent believed that the medication really did reduce illness.

Then for a randomly selected subsample, the researchers supplemented the description of the drug trial with a simple chart. But here’s the kicker: That chart contained no new information; it simply repeated the information in the original vignette, with a tall bar illustrating that 87 percent of the control group had the illness, and a shorter bar showing that that number fell to 47 percent for those who took the drug.